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Groups > comp.lang.c > #43061 > unrolled thread

Constant strings

Started by"BartC" <bc@freeuk.com>
First post2014-04-18 11:45 +0100
Last post2014-04-21 09:08 +0200
Articles 20 on this page of 280 — 25 participants

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Contents

  Constant strings "BartC" <bc@freeuk.com> - 2014-04-18 11:45 +0100
    Re: Constant strings Richard Damon <Richard@Damon-Family.org> - 2014-04-18 07:34 -0400
    Re: Constant strings G G <gdotone@gmail.com> - 2014-04-18 05:23 -0700
      Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-18 17:16 +0100
        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-18 11:08 -0700
        Re: Constant strings G G <gdotone@gmail.com> - 2014-04-18 13:11 -0700
    Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-18 10:21 -0400
      Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-18 08:45 -0700
      Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-18 16:48 +0100
        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-18 09:21 -0700
        Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-19 09:09 +1200
          Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-18 23:53 +0100
            Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-18 23:06 +0000
              Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-19 03:57 -0700
                Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-19 23:41 +1200
                  Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-19 06:21 -0700
                    Re: Constant strings Barry Schwarz <schwarzb@dqel.com> - 2014-04-19 10:04 -0700
                      Re: Constant strings Barry Schwarz <schwarzb@dqel.com> - 2014-04-19 16:54 -0700
                      Re: Constant strings Seungbeom Kim <musiphil@bawi.org> - 2014-04-19 17:54 -0700
                    Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-19 13:20 -0700
                      Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-19 23:32 +0100
                        Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-19 23:38 +0000
                        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-19 17:28 -0700
                          Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-20 10:53 +0100
                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-20 14:29 -0700
                              Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-20 23:41 +0100
                                Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-21 11:14 +1200
                                  Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-21 13:05 +0100
                                    Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-21 11:11 -0700
                                Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-20 19:44 -0700
                                  Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-21 10:51 +0100
                                    Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-21 13:29 -0400
                                    Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-21 11:04 -0700
                                      Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 11:31 +0100
                                        Re: Constant strings Martin Shobe <martin.shobe@yahoo.com> - 2014-04-22 06:24 -0500
                                          Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 13:34 +0100
                                            Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-22 09:19 -0400
                                              Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 15:00 +0100
                                                Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 07:53 -0700
                                                Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-22 12:48 -0400
                                        Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-22 07:28 -0400
                                          Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-22 05:46 -0700
                                        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 07:45 -0700
                                          Re: Constant strings Ike Naar <ike@iceland.freeshell.org> - 2014-04-22 16:34 +0000
                                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 10:10 -0700
                                        Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-22 11:50 -0500
                                          Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 18:48 +0100
                                            Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-22 14:02 -0400
                                              Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 19:48 +0100
                                                Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-22 15:28 -0400
                                                Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-22 19:48 -0500
                                                  Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-23 11:56 +0100
                                                    Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-23 12:59 +0100
                                                      Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-23 08:21 -0400
                                                        Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-23 14:09 +0100
                                                        Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-23 14:19 +0100
                                                    Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-23 08:40 -0400
                                                      Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-23 11:56 -0400
                                                        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-23 11:10 -0700
                                                          Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-23 19:19 -0500
                                                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-23 19:19 -0700
                                                            Re: Constant strings Robert Wessel <robertwessel2@yahoo.com> - 2014-04-23 23:53 -0500
                                                              Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-24 11:55 +0000
                                                              Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-24 11:27 -0500
                                                                Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-24 20:03 +0000
                                                                  Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-24 17:16 -0500
                                                      Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-23 17:39 +0100
                                                        Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-23 13:06 -0400
                                                          Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-23 10:25 -0700
                                                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-23 11:30 -0700
                                                              Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-23 20:55 +0000
                                                              Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-23 21:53 -0700
                                                                Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-24 17:05 +1200
                                                                  Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-24 00:59 -0700
                                                          Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-23 18:39 +0100
                                                            Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-23 14:53 -0400
                                                              Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-23 21:09 +0100
                                                                Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-23 19:23 -0400
                                                                Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-25 10:52 -0500
                                                            Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-23 19:36 -0500
                                                              Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-24 10:37 +0100
                                                                Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-24 07:45 -0400
                                                                  Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-24 13:15 +0100
                                                                    Re: Constant strings Martin Shobe <martin.shobe@yahoo.com> - 2014-04-24 08:33 -0500
                                                                    Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-24 09:47 -0400
                                                                      Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-24 15:09 +0100
                                                                        Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-24 12:07 -0400
                                                                          Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-24 18:23 +0100
                                                                            Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-24 14:49 -0400
                                                                          Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-24 13:48 -0500
                                                                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-24 12:32 -0700
                                                                              Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-24 23:57 -0500
                                                                                Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-25 08:31 -0400
                                                                                  Re: Constant strings Martin Shobe <martin.shobe@yahoo.com> - 2014-04-25 09:51 -0500
                                                                                    Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-25 16:45 +0100
                                                                                      Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-25 09:07 -0700
                                                                                        Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-25 17:33 +0100
                                                                                          Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-25 11:38 -0700
                                                                                      Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-25 11:42 -0700
                                                                                  Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-25 10:58 -0500
                                                                                    Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-25 11:29 -0700
                                                                                      Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-25 15:10 -0400
                                                                                        Re: Constant strings Martin Shobe <martin.shobe@yahoo.com> - 2014-04-25 19:06 -0500
                                                                                          Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-26 05:39 -0400
                                                                                            Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-26 04:07 -0700
                                                                                              Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-26 12:50 +0100
                                                                                                Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-26 05:03 -0700
                                                                                                  Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-26 11:23 -0700
                                                                                                    Re: Constant strings gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-26 19:13 +0000
                                                                                                      Re: Constant strings Richard <rgrdev_@gmail.com> - 2014-04-26 23:54 +0200
                                                                                                        Re: Constant strings Richard Damon <Richard@Damon-Family.org> - 2014-04-26 18:47 -0400
                                                                                                          Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-26 23:01 +0000
                                                                                                          Re: Constant strings Seungbeom Kim <musiphil@bawi.org> - 2014-04-26 18:09 -0700
                                                                                                            Re: Constant strings gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-27 01:22 +0000
                                                                                                              Re: Constant strings Richard <rgrdev_@gmail.com> - 2014-04-27 04:09 +0200
                                                                                                            Re: Constant strings David Thompson <dave.thompson2@verizon.net> - 2014-05-25 16:44 -0400
                                                                                                              Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-05-25 14:43 -0700
                                                                                                          Re: Constant strings Richard <rgrdev_@gmail.com> - 2014-04-27 04:09 +0200
                                                                                                            Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-27 05:36 +0000
                                                                                                          Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-27 06:42 -0700
                                                                                                      Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-27 02:42 +0000
                                                                                                        Re: Constant strings Richard <rgrdev_@gmail.com> - 2014-04-27 04:45 +0200
                                                                                                          Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-27 14:13 -0500
                                                                                                            Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-27 20:11 +0000
                                                                                                              Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-28 03:22 +0100
                                                                                                                Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-28 10:00 +0100
                                                                                                                  Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-28 11:24 +0100
                                                                                                                    Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-28 12:30 +0000
                                                                                                                      Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-28 13:58 +0100
                                                                                                                  Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-28 12:22 +0000
                                                                                                                  Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-28 08:53 -0700
                                                                                                                    Re: Constant strings gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-28 16:10 +0000
                                                                                                                    Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-28 18:11 +0000
                                                                                                                      Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-28 11:34 -0700
                                                                                                                    Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-28 19:01 +0000
                                                                                                                Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-28 11:06 +0000
                                                                                                                  Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-28 12:48 +0100
                                                                                                                    Re: Constant strings Richard Damon <Richard@Damon-Family.org> - 2014-04-28 08:11 -0400
                                                                                                                    Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-28 14:04 +0000
                                                                                                                  Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-28 12:55 +0100
                                                                                                                    Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-28 13:23 +0100
                                                                                                                      Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-28 13:47 +0100
                                                                                                                      Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-28 06:01 -0700
                                                                                                                      Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-29 08:43 +1200
                                                                                                                        Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-28 21:08 +0000
                                                                                                                          Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-29 09:32 +1200
                                                                                                                            Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-28 22:41 +0100
                                                                                                                              Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-28 22:00 +0000
                                                                                                                                Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-28 23:18 +0100
                                                                                                                                  Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-28 15:43 -0700
                                                                                                                                    Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-28 23:23 +0000
                                                                                                                                  Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-28 22:47 +0000
                                                                                                                                  Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-28 23:17 +0000
                                                                                                                                    Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-29 01:18 +0100
                                                                                                                                      Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-29 00:31 +0000
                                                                                                                                        Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-29 01:58 +0100
                                                                                                                                          Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-29 01:13 +0000
                                                                                                                                            Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-29 03:19 +0100
                                                                                                                                              Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-29 03:31 +0000
                                                                                                                                              Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-29 04:21 +0000
                                                                                                                                                Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-29 04:29 +0000
                                                                                                                                                  Re: Constant strings Richard <rgrdev_@gmail.com> - 2014-04-29 09:14 +0200
                                                                                                                                                    Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-29 14:05 +0100
                                                                                                                                        Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-29 00:37 -0700
                                                                                                                                          Re: Constant strings Richard <rgrdev_@gmail.com> - 2014-04-29 13:36 +0200
                                                                                                                                            Re: Constant strings ralph <nt_consulting@yahoo.com> - 2014-04-29 07:49 -0500
                                                                                                                                          Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-29 06:28 -0700
                                                                                                                                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-29 07:37 -0700
                                                                                                                                              Re: Constant strings David Brown <david.brown@hesbynett.no> - 2014-04-29 17:15 +0200
                                                                                                                                                Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-29 20:58 +0000
                                                                                                                                                  Re: Constant strings David Brown <david.brown@hesbynett.no> - 2014-04-30 10:16 +0200
                                                                                                                                              Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-29 16:04 +0000
                                                                                                                                                Re: Constant strings gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-29 16:10 +0000
                                                                                                                                                  Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-29 09:58 -0700
                                                                                                                                                    Re: Constant strings Richard <rgrdev_@gmail.com> - 2014-04-30 12:46 +0200
                                                                                                                                            Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-29 14:51 +0000
                                                                                                                                              Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-29 16:05 +0000
                                                                                                                                      Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-29 01:53 +0000
                                                                                                                                Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-28 23:11 +0000
                                                                                                                                  Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-28 23:29 +0000
                                                                                                                                    Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-29 00:18 +0000
                                                                                                                            Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-28 21:52 +0000
                                                                                                                              Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-28 23:08 +0100
                                                                                                                                Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-28 22:31 +0000
                                                                                                                                  Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-29 00:54 +0100
                                                                                                                        Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-28 23:10 +0100
                                                                                                                          Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-29 11:28 +1200
                                                                                                        Re: Constant strings gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-27 06:31 +0000
                                                                                            Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-26 12:27 +0100
                                                                                              Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-26 13:11 +0100
                                                                                                Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-26 13:50 +0100
                                                                                                Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-26 11:26 -0700
                                                                                                  Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-27 02:21 +0100
                                                                                            Re: Constant strings Martin Shobe <martin.shobe@yahoo.com> - 2014-04-26 08:05 -0500
                                                                                              Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-26 11:39 -0700
                                                                                                Re: Constant strings Martin Shobe <martin.shobe@yahoo.com> - 2014-04-26 16:27 -0500
                                                                                                Re: Constant strings Ian Zimmerman <itz@buug.org> - 2014-04-27 10:46 -0700
                                                                                              Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-26 22:46 -0400
                                                                                                Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-27 10:08 +0100
                                                                                                  Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-27 07:35 -0700
                                                                                                    Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-27 16:35 +0100
                                                                                                      Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-27 12:28 -0700
                                                                                                Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-27 12:36 +0100
                                                                                                  Re: Constant strings James Kuyper <jameskuyper@verizon.net> - 2014-04-27 23:14 -0400
                                                                        Re: Constant strings Seungbeom Kim <musiphil@bawi.org> - 2014-04-26 18:03 -0700
                                                                          Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-27 02:33 +0100
                                                                      Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-24 07:49 -0700
                                                                        Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-25 03:03 +0100
                                                                          Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-25 22:50 +0100
                                                                        Re: Constant strings Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2014-04-24 20:20 -0600
                                                                          Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-24 23:31 -0700
                                                                            Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-25 15:24 +0100
                                                                              Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-25 08:31 -0700
                                                                    Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-24 07:58 -0700
                                                                  Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-26 13:38 +0100
                                                                    Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-26 11:50 -0700
                                                                Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-24 07:42 -0700
                                                                  Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-24 08:43 -0700
                                                        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-23 11:28 -0700
                                                          Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-23 18:42 +0000
                                                            Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-24 14:03 -0500
                                                        Re: Constant strings glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-23 20:49 +0000
                                                          Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-23 21:21 +0000
                                                    Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-23 10:50 -0500
                                            Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-22 19:41 -0500
                                    Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 09:43 -0700
                                      Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 18:19 +0100
                                        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 11:45 -0700
                                          Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 20:01 +0100
                                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 12:19 -0700
                                            Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-23 11:01 -0500
                                        Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-22 15:21 -0500
                          Re: Constant strings Richard <rgrdev_@gmail.com> - 2014-04-20 11:08 +0100
                      Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-22 02:26 -0700
                        Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-22 21:36 +1200
                        Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 13:14 +0100
                        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 07:25 -0700
                          Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-22 08:29 -0700
                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 09:35 -0700
                              Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-22 09:54 -0700
                                Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 10:17 -0700
                                  Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-22 10:31 -0700
                      Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-22 02:33 -0700
                        Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-22 21:37 +1200
                          Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-22 07:17 -0700
                Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-19 13:42 +0100
                Re: Constant strings Ike Naar <ike@iceland.freeshell.org> - 2014-04-19 15:42 +0000
                  Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-19 16:19 +0000
                Re: Constant strings Seungbeom Kim <musiphil@bawi.org> - 2014-04-19 17:47 -0700
            Re: Constant strings Stephen Sprunk <stephen@sprunk.org> - 2014-04-22 11:00 -0500
              Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 18:36 +0100
                Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-23 09:38 +1200
                  Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-22 23:25 +0100
                    Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-23 10:48 +1200
                      Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-23 12:37 +0100
                        Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-23 13:47 +0100
                          Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-23 14:03 +0100
                        Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-24 09:14 +1200
                          Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-23 23:37 +0100
                            Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-24 10:54 +1200
                              Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-24 00:52 +0100
                                Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-24 01:04 +0000
                                  Re: Constant strings Ian Collins <ian-news@hotmail.com> - 2014-04-24 13:16 +1200
                                Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-23 19:14 -0700
                              Re: Constant strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-24 03:41 +0100
                            Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-23 16:04 -0700
    Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-18 08:53 -0700
      Re: Constant strings Tim Rentsch <txr@alumni.caltech.edu> - 2014-04-20 16:02 -0700
    Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-18 16:13 +0000
      Re: Constant strings "BartC" <bc@freeuk.com> - 2014-04-18 18:34 +0100
        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-18 11:06 -0700
        Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-18 18:54 +0000
          Re: Constant strings Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-18 14:15 -0700
    Re: Constant strings Rosario193 <Rosario@invalid.invalid> - 2014-04-20 20:15 +0200
      Re: Constant strings Rosario193 <Rosario@invalid.invalid> - 2014-04-20 22:13 +0200
        Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-20 14:31 -0700
      Re: Constant strings Keith Thompson <kst-u@mib.org> - 2014-04-20 14:30 -0700
        Re: Constant strings Rosario193 <Rosario@invalid.invalid> - 2014-04-21 02:43 +0200
          Re: Constant strings Kaz Kylheku <kaz@kylheku.com> - 2014-04-21 03:12 +0000
            Re: Constant strings Rosario193 <Rosario@invalid.invalid> - 2014-04-21 09:08 +0200

Page 8 of 14 — ← Prev page 1 … 6 7 [8] 9 10 … 14  Next page →


#43711

From"BartC" <bc@freeuk.com>
Date2014-04-28 13:23 +0100
Message-ID<hLr7v.164833$sa2.43402@fx33.am4>
In reply to#43708

"Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message
news:0.d9dc063c172708b96ce8.20140428125517BST.87r44h1xei.fsf@bsb.me.uk...
> glen herrmannsfeldt <gah@ugcs.caltech.edu> writes:
>
>> Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>> <snip, I wrote>
>>>> Passing a pointer by value isn't much different, other than name,
>>>> from pass by reference.
>>
>>> I suppose it depends on what you are used to.  In the "olden days" (the
>>> 70 and 80) when reading the reference manual for one of the seemingly
>>> thousands of new programming languages that were popping up at the time,
>>> if I read the phrase "arguments are passed by reference" or was told
>>> that some syntax caused a argument to be "passed by reference", I would
>>> assume that I need do nothing special in either the call or the function
>>> body to get this effect.  In C, I must arrange for the pointer to
>>> passed, and I must pepper the function body with *s to refer to the
>>> referenced object.
>>
>> For arrays, C makes it look pretty close, especially if you
>> declare s[] instead of *s. (And as long as you don't change s.)
>
> See my reply to BartC: calling this pass by reference just complicates
> the description of a language that has enough special cases already!
>
>> For scalars, yes, you put *s all over. Is there a better way?
>
> Better in what sense?  Languages that actually have pass by reference
> make it simpler, but the whole idea is in disrepute, so you might be
> asking about ways to make a bad thing badder.

If we're talking about C, then it doesn't /have/ formal pass-by-reference,
but it /uses/ pass-by-reference extensively through explicit use of
pointers.

In which case he might mean a better way of doing the latter.

As for being in disrepute, it seems unlikely to me that modern languages are
all embracing pass-by-value exclusively. They will use pass-by-reference or
equivalent behind the scenes, because it's more efficient for non-primitive
types, but they might also introduce restrictions such as immutability to
avoid this causing too many unexpected problems.

-- 
Bartc 

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#43714

FromBen Bacarisse <ben.usenet@bsb.me.uk>
Date2014-04-28 13:47 +0100
Message-ID<0.dfb52f6af266482f9507.20140428134734BST.87iopt1uzd.fsf@bsb.me.uk>
In reply to#43711
"BartC" <bc@freeuk.com> writes:

> "Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message
> news:0.d9dc063c172708b96ce8.20140428125517BST.87r44h1xei.fsf@bsb.me.uk...
>> glen herrmannsfeldt <gah@ugcs.caltech.edu> writes:
>>
>>> Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>>> <snip, I wrote>
>>>>> Passing a pointer by value isn't much different, other than name,
>>>>> from pass by reference.
>>>
>>>> I suppose it depends on what you are used to.  In the "olden days" (the
>>>> 70 and 80) when reading the reference manual for one of the seemingly
>>>> thousands of new programming languages that were popping up at the time,
>>>> if I read the phrase "arguments are passed by reference" or was told
>>>> that some syntax caused a argument to be "passed by reference", I would
>>>> assume that I need do nothing special in either the call or the function
>>>> body to get this effect.  In C, I must arrange for the pointer to
>>>> passed, and I must pepper the function body with *s to refer to the
>>>> referenced object.
>>>
>>> For arrays, C makes it look pretty close, especially if you
>>> declare s[] instead of *s. (And as long as you don't change s.)
>>
>> See my reply to BartC: calling this pass by reference just complicates
>> the description of a language that has enough special cases already!
>>
>>> For scalars, yes, you put *s all over. Is there a better way?
>>
>> Better in what sense?  Languages that actually have pass by reference
>> make it simpler, but the whole idea is in disrepute, so you might be
>> asking about ways to make a bad thing badder.
>
> If we're talking about C, then it doesn't /have/ formal pass-by-reference,
> but it /uses/ pass-by-reference extensively through explicit use of
> pointers.

... which are passed by value.  I think you are keen to use the term
because it suits something about the way you think about programming
languages.  For me, borrowing a phrase with a specific meaning ("pass by
reference") and using with a rather vague modifier ("uses") just makes a
mess.  Do you object to the simple claim the C does not pass any
function arguments by reference?

-- 
Ben.

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#43716

FromMalcolm McLean <malcolm.mclean5@btinternet.com>
Date2014-04-28 06:01 -0700
Message-ID<407cb120-ad29-4d8f-a66a-8af9c7857c58@googlegroups.com>
In reply to#43711
On Monday, April 28, 2014 1:23:15 PM UTC+1, Bart wrote:
> 
> As for being in disrepute, it seems unlikely to me that modern languages are
> all embracing pass-by-value exclusively. They will use pass-by-reference or
> equivalent behind the scenes, because it's more efficient for non-primitive
> types, but they might also introduce restrictions such as immutability to
> avoid this causing too many unexpected problems.
> 
So called closures are getting popular.

This works along the lines of

function foo
{
  variable foo_scope =0;

  function bar
  {
    foo_scope = 42;
  }

  callsomethingthattakesafunction(bar);

  /* foo_cope now 42 */
}

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#43725

FromIan Collins <ian-news@hotmail.com>
Date2014-04-29 08:43 +1200
Message-ID<bs7srkFua2rU1@mid.individual.net>
In reply to#43711
BartC wrote:
>
> If we're talking about C, then it doesn't /have/ formal pass-by-reference,
> but it /uses/ pass-by-reference extensively through explicit use of
> pointers.

You should spend some time with a statically typed language that does 
use pass by reference.  That might help you understand the differences.

For example in C++:

# cat x.cc
void ptr( const char i[5] ) {}

void ref( const char (&i)[5] ) {}

int main()
{
   ptr("not 5 chars");  // Will decay to pointer.
   ref("not 5 chars");  // Must be correct type.
}

# CC x.cc
"x.cc", line 8: Error: Formal argument i of type const char(&)[5] in 
call to ref(const char(&)[5]) is being passed const char[12].


-- 
Ian Collins

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#43731

FromKaz Kylheku <kaz@kylheku.com>
Date2014-04-28 21:08 +0000
Message-ID<20140428135713.835@kylheku.com>
In reply to#43725
On 2014-04-28, Ian Collins <ian-news@hotmail.com> wrote:
> BartC wrote:
>>
>> If we're talking about C, then it doesn't /have/ formal pass-by-reference,
>> but it /uses/ pass-by-reference extensively through explicit use of
>> pointers.
>
> You should spend some time with a statically typed language that does 
> use pass by reference.  That might help you understand the differences.

I don't see any real misunderstanding in the above paragraph.

> For example in C++:
>
> # cat x.cc
> void ptr( const char i[5] ) {}
>
> void ref( const char (&i)[5] ) {}
>
> int main()
> {
>    ptr("not 5 chars");  // Will decay to pointer.
>    ref("not 5 chars");  // Must be correct type.
> }

This is apples and oranges: pointer to element, versus reference to array.

In C with pointers to array (the "other" way to pass the string by
reference):

  void ptr2(char (*i)[5])
  {
  }

  int main(void)
  {
    ptr2(&"abcd");   /* okay */
    ptr2(&"abcde");  /* type mismatch */
    return 0;
  }

Hmm, never address-of on a string literal before. GCC likes it as a C90 compiler
(with -Wall -W -ansi -pedantic); I can't think of a reason why it wouldn't be
allowed.

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#43740

FromIan Collins <ian-news@hotmail.com>
Date2014-04-29 09:32 +1200
Message-ID<bs7vmgFua2rU2@mid.individual.net>
In reply to#43731
Kaz Kylheku wrote:
> On 2014-04-28, Ian Collins <ian-news@hotmail.com> wrote:
>> BartC wrote:
>>>
>>> If we're talking about C, then it doesn't /have/ formal pass-by-reference,
>>> but it /uses/ pass-by-reference extensively through explicit use of
>>> pointers.
>>
>> You should spend some time with a statically typed language that does
>> use pass by reference.  That might help you understand the differences.
>
> I don't see any real misunderstanding in the above paragraph.
>
>> For example in C++:
>>
>> # cat x.cc
>> void ptr( const char i[5] ) {}
>>
>> void ref( const char (&i)[5] ) {}
>>
>> int main()
>> {
>>     ptr("not 5 chars");  // Will decay to pointer.
>>     ref("not 5 chars");  // Must be correct type.
>> }
>
> This is apples and oranges: pointer to element, versus reference to array.

The point was to illustrate passing an array by reference compare to 
what some claim is passing an array by reference (through the pointer to 
it's first element) in C.

> In C with pointers to array (the "other" way to pass the string by
> reference):
>
>    void ptr2(char (*i)[5])
>    {
>    }

But that isn't really passing by reference as you have to dereference i 
before using it as an array.

-- 
Ian Collins

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#43744

FromBen Bacarisse <ben.usenet@bsb.me.uk>
Date2014-04-28 22:41 +0100
Message-ID<0.b0b84710755fd4ad0fc9.20140428224121BST.87r44hyvwe.fsf@bsb.me.uk>
In reply to#43740
Ian Collins <ian-news@hotmail.com> writes:

> Kaz Kylheku wrote:
<snip>
>> In C with pointers to array (the "other" way to pass the string by
>> reference):
>>
>>    void ptr2(char (*i)[5])
>>    {
>>    }
>
> But that isn't really passing by reference as you have to dereference
> i before using it as an array.

This isn't pass by reference because an assignment to i, inside ptr2,
will not alter the object (if there was one) used as an argument in the
caller!

-- 
Ben.

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#43751

FromKaz Kylheku <kaz@kylheku.com>
Date2014-04-28 22:00 +0000
Message-ID<20140428145713.974@kylheku.com>
In reply to#43744
On 2014-04-28, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
> Ian Collins <ian-news@hotmail.com> writes:
>
>> Kaz Kylheku wrote:
><snip>
>>> In C with pointers to array (the "other" way to pass the string by
>>> reference):
>>>
>>>    void ptr2(char (*i)[5])
>>>    {
>>>    }
>>
>> But that isn't really passing by reference as you have to dereference
>> i before using it as an array.
>
> This isn't pass by reference because an assignment to i, inside ptr2,
> will not alter the object (if there was one) used as an argument in the
> caller!

Assignment to i resulting in changing a variable in the caller,
is a feature of "pass by transparent/invisible reference".

"Pass by explicit/visible reference" requires that a dereferencing
operator be applied to the reference to designate the caller's object
from which the reference was obtained.

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#43756

FromBen Bacarisse <ben.usenet@bsb.me.uk>
Date2014-04-28 23:18 +0100
Message-ID<0.5984a1ef4a744c952883.20140428231858BST.87eh0hyu5p.fsf@bsb.me.uk>
In reply to#43751
Kaz Kylheku <kaz@kylheku.com> writes:

> On 2014-04-28, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>> Ian Collins <ian-news@hotmail.com> writes:
>>
>>> Kaz Kylheku wrote:
>><snip>
>>>> In C with pointers to array (the "other" way to pass the string by
>>>> reference):
>>>>
>>>>    void ptr2(char (*i)[5])
>>>>    {
>>>>    }
>>>
>>> But that isn't really passing by reference as you have to dereference
>>> i before using it as an array.
>>
>> This isn't pass by reference because an assignment to i, inside ptr2,
>> will not alter the object (if there was one) used as an argument in the
>> caller!
>
> Assignment to i resulting in changing a variable in the caller,
> is a feature of "pass by transparent/invisible reference".

Did you just make that up or is it now a widely used term?  I do like
to try to keep up if I can.

> "Pass by explicit/visible reference" requires that a dereferencing
> operator be applied to the reference to designate the caller's object
> from which the reference was obtained.

No more than any assignment does.  Some compilers do indeed generate an
address and de-reference it, but they don't have to.  It is not
required in all cases.  Fortran compilers used to be very good at
spotting aliasing and (in effect) exchanging the assignment to the
parameter for an assignment to the argument.

-- 
Ben.

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#43763

FromMalcolm McLean <malcolm.mclean5@btinternet.com>
Date2014-04-28 15:43 -0700
Message-ID<87476f3b-38ac-4488-b4f4-367fd65cf58d@googlegroups.com>
In reply to#43756
On Monday, April 28, 2014 11:18:58 PM UTC+1, Ben Bacarisse wrote:
> 
> No more than any assignment does.  Some compilers do indeed generate an
> address and de-reference it, but they don't have to.  It is not
> required in all cases.  Fortran compilers used to be very good at
> spotting aliasing and (in effect) exchanging the assignment to the
> parameter for an assignment to the argument.
> 
Exactly. Fortran compilers also don't need to worry about pointer aliasing.
But whilst its superbly efficient, it's also a lot harder to keep track of
which variables are being set where, and there's no sort of hierarchy 
or grouping such as structures can impose. So it's less flexible, less
easy to write programs whose main objective is data manipulation rather
than calculations.
You interface Fortran with C by passing pointers, however. A C function
that is callable from Fortran takes pointers as parameters, a Fortran
function callable from C is passed pointers.

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#43774

Fromglen herrmannsfeldt <gah@ugcs.caltech.edu>
Date2014-04-28 23:23 +0000
Message-ID<ljmnsl$8rb$1@speranza.aioe.org>
In reply to#43763
Malcolm McLean <malcolm.mclean5@btinternet.com> wrote:

(snip on call by reference and Fortran)

> You interface Fortran with C by passing pointers, however. A C function
> that is callable from Fortran takes pointers as parameters, a Fortran
> function callable from C is passed pointers.

Actually, Fortran now has the VALUE attribute, and so can also do
call by value, when needed. It isn't the default, though.

With the C interoprability feature now in Fortran, you can easily
call between Fortran and C. If you pass an argument, and don't
use the VALUE attribute, then a pointer is passed. You can also
directly pass a TYPE(C_PTR) or the return value of C_LOC() by
value to a called C function.

-- glen

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#43766

FromKaz Kylheku <kaz@kylheku.com>
Date2014-04-28 22:47 +0000
Message-ID<20140428153226.858@kylheku.com>
In reply to#43756
On 2014-04-28, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
> Kaz Kylheku <kaz@kylheku.com> writes:
>
>> On 2014-04-28, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>>> Ian Collins <ian-news@hotmail.com> writes:
>>>
>>>> Kaz Kylheku wrote:
>>><snip>
>>>>> In C with pointers to array (the "other" way to pass the string by
>>>>> reference):
>>>>>
>>>>>    void ptr2(char (*i)[5])
>>>>>    {
>>>>>    }
>>>>
>>>> But that isn't really passing by reference as you have to dereference
>>>> i before using it as an array.
>>>
>>> This isn't pass by reference because an assignment to i, inside ptr2,
>>> will not alter the object (if there was one) used as an argument in the
>>> caller!
>>
>> Assignment to i resulting in changing a variable in the caller,
>> is a feature of "pass by transparent/invisible reference".
>
> Did you just make that up or is it now a widely used term?  I do like
> to try to keep up if I can.

I made it up. I didn't make up "transparent", "invisible" or "reference" of
course and aren't using them in any non-obvious way.

>> "Pass by explicit/visible reference" requires that a dereferencing
>> operator be applied to the reference to designate the caller's object
>> from which the reference was obtained.
>
> No more than any assignment does.

Yes; and that is because there actually isn't any special "pass by"
data flow that is for functions only. Reducing an expression to a value
and using it to initialize a newly instantiated variable in a new function
invocation is a data flow. Assignment is another example of a data flow.
Both of these can be regarded as "passing" something.

Any time in C a reference to an object moves from one place in the program
graph to another, we use a value to represent that data flow, and have to
manually insert operators to source that kind of flow, and to recover the
referenced value at various "sinks" reached by that value.

[toc] | [prev] | [next] | [standalone]


#43772

Fromglen herrmannsfeldt <gah@ugcs.caltech.edu>
Date2014-04-28 23:17 +0000
Message-ID<ljmnic$89u$1@speranza.aioe.org>
In reply to#43756
Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:

(snip)

> No more than any assignment does.  Some compilers do indeed generate an
> address and de-reference it, but they don't have to.  It is not
> required in all cases.  Fortran compilers used to be very good at
> spotting aliasing and (in effect) exchanging the assignment to the
> parameter for an assignment to the argument.

I am not so sure what that means, but Fortran has much stricter
aliasing rules than C.

For one, Fortran doesn't require call by reference, but also allows
for call by value result (also known as copy-in/copy-out). 
The difference is very obvious in some aliasing cases.

I have known Fortran compilers where the addresses of the arguments
were passed, and the called routine copied the values in at the
beginning, and copied them back before returning. On some machines,
access to local variables is much faster than the indirect addressing
to access through a reference. Though the actual gain depends on
how often it is accessed.

-- glen

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#43790

FromBen Bacarisse <ben.usenet@bsb.me.uk>
Date2014-04-29 01:18 +0100
Message-ID<0.0afae8b0f55afa8aeaad.20140429011816BST.871twhyomv.fsf@bsb.me.uk>
In reply to#43772
glen herrmannsfeldt <gah@ugcs.caltech.edu> writes:

> Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>
> (snip)
>
>> No more than any assignment does.  Some compilers do indeed generate an
>> address and de-reference it, but they don't have to.  It is not
>> required in all cases.  Fortran compilers used to be very good at
>> spotting aliasing and (in effect) exchanging the assignment to the
>> parameter for an assignment to the argument.
>
> I am not so sure what that means, but Fortran has much stricter
> aliasing rules than C.

My point was that when a Fortran compiler is using call by reference, it
is not required to pass a pointer and then dereference it.  That was the
claim Kaz made that I was replying to.  In a fragment like this:

  J = 99
  CALL T(J)
  ...
  SUBROUTINE T(I)
  I = 42
  END

the compiler can generate the same code (modulo the constant) for the
assignment to I as it does for the assignment to J.  Some compilers
might pass an address then dereference it, but they are not required to
do that in all situations.

My remark "no more than any assignment does" is just a nod to the fact
that any assignment implicitly involves an indirect access, but there
need be no extra work simply because of the argument passing semantics.

<snip>
-- 
Ben.

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#43793

FromKaz Kylheku <kaz@kylheku.com>
Date2014-04-29 00:31 +0000
Message-ID<20140428172735.291@kylheku.com>
In reply to#43790
On 2014-04-29, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
> glen herrmannsfeldt <gah@ugcs.caltech.edu> writes:
>
>> Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>>
>> (snip)
>>
>>> No more than any assignment does.  Some compilers do indeed generate an
>>> address and de-reference it, but they don't have to.  It is not
>>> required in all cases.  Fortran compilers used to be very good at
>>> spotting aliasing and (in effect) exchanging the assignment to the
>>> parameter for an assignment to the argument.
>>
>> I am not so sure what that means, but Fortran has much stricter
>> aliasing rules than C.
>
> My point was that when a Fortran compiler is using call by reference, it
> is not required to pass a pointer and then dereference it.  That was the
> claim Kaz made that I was replying to.  In a fragment like this:
>
>   J = 99
>   CALL T(J)
>   ...
>   SUBROUTINE T(I)
>   I = 42
>   END
>
> the compiler can generate the same code (modulo the constant) for the
> assignment to I as it does for the assignment to J.  Some compilers
> might pass an address then dereference it, but they are not required to
> do that in all situations.

How about:

  inline assign_42(int *i)
  {
    *i = 42;
  }

  assign_42(&x); /* generates the same code as x = 42: no pointer */

If T is an external function in a separately compiled module,
I don't see how Fortran can achieve it without a reference datum
being passed indicating the location of I.
(Or worse: call-by-name thunk or its ilk.)

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#43794

FromBen Bacarisse <ben.usenet@bsb.me.uk>
Date2014-04-29 01:58 +0100
Message-ID<0.85035c67accfe11b5007.20140429015837BST.87r44hx876.fsf@bsb.me.uk>
In reply to#43793
Kaz Kylheku <kaz@kylheku.com> writes:

> On 2014-04-29, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>> glen herrmannsfeldt <gah@ugcs.caltech.edu> writes:
>>
>>> Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>>>
>>> (snip)
>>>
>>>> No more than any assignment does.  Some compilers do indeed generate an
>>>> address and de-reference it, but they don't have to.  It is not
>>>> required in all cases.  Fortran compilers used to be very good at
>>>> spotting aliasing and (in effect) exchanging the assignment to the
>>>> parameter for an assignment to the argument.
>>>
>>> I am not so sure what that means, but Fortran has much stricter
>>> aliasing rules than C.
>>
>> My point was that when a Fortran compiler is using call by reference, it
>> is not required to pass a pointer and then dereference it.  That was the
>> claim Kaz made that I was replying to.  In a fragment like this:
>>
>>   J = 99
>>   CALL T(J)
>>   ...
>>   SUBROUTINE T(I)
>>   I = 42
>>   END
>>
>> the compiler can generate the same code (modulo the constant) for the
>> assignment to I as it does for the assignment to J.  Some compilers
>> might pass an address then dereference it, but they are not required to
>> do that in all situations.
>
> How about:
>
>   inline assign_42(int *i)
>   {
>     *i = 42;
>   }
>
>   assign_42(&x); /* generates the same code as x = 42: no pointer */

Yes, and even when the function is not inline.  Some compilers are very
clever.

> If T is an external function in a separately compiled module,
> I don't see how Fortran can achieve it without a reference datum
> being passed indicating the location of I.
> (Or worse: call-by-name thunk or its ilk.)

Neither can I (thought I would never second guess some clever linker
optimisation, especially given old Fortran's non-support of recursion).
I think we agree on the technicalities.  Neither C nor Fortran require
passing an explicit pointer (even when it's explicit in the C code) and
there are situations in which neither of us can think of any reasonable
alternative for either language.

Trying to characterise a high-level language facility by what is
operationally required is, to my mind, unhelpful.

-- 
Ben.

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#43795

FromKaz Kylheku <kaz@kylheku.com>
Date2014-04-29 01:13 +0000
Message-ID<20140428180307.117@kylheku.com>
In reply to#43794
On 2014-04-29, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
> Trying to characterise a high-level language facility by what is
> operationally required is, to my mind, unhelpful.

What's the difference between that and using an abstract machine model
which can be optimized?

If we are passing by reference, a reference (whatever that is) is operationally
required; that is fine, isn't it?

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#43797

FromBen Bacarisse <ben.usenet@bsb.me.uk>
Date2014-04-29 03:19 +0100
Message-ID<0.3ce501fc5ffd53f1c1f1.20140429031911BST.87k3a8yj1c.fsf@bsb.me.uk>
In reply to#43795
Kaz Kylheku <kaz@kylheku.com> writes:

> On 2014-04-29, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
>> Trying to characterise a high-level language facility by what is
>> operationally required is, to my mind, unhelpful.
>
> What's the difference between that and using an abstract machine model
> which can be optimized?
>
> If we are passing by reference, a reference (whatever that is) is
> operationally required; that is fine, isn't it?

Yes, that's fine, but I don't think that was ever in doubt.  That
passing by reference requires, in some abstract models, some form of
reference seems so uncontroversial that I can only assume that what you
said at some point seemed to me to be more than that.  Otherwise, I can't
imagine why I commented.  Anyway, I prefer to agree on this point than
to go back and try see why I disagreed.

On the matter of terminology, I am not persuaded that simply passing a
pointer should be called pass by reference.  I realise that you won't be
persuaded, so we can just agree to differ.

-- 
Ben.

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#43802

Fromglen herrmannsfeldt <gah@ugcs.caltech.edu>
Date2014-04-29 03:31 +0000
Message-ID<ljn6do$4bj$1@speranza.aioe.org>
In reply to#43797
Stefan Ram <ram@zedat.fu-berlin.de> wrote:
 
>  It always refers to the /argument expression/. When the
>  argument value already is an address of an object o, as in
 
> f( &o )
 
>  , then pass-by-reference would require a reference to »&o«
>  (not to »o«), because the argument expression is »&o« and
>  not »o«. C only has pass-by-value in function calls. Also
>  in »f( &o )«, the /value/ of »&o« is passed.
 
>  One can emulate some aspects of »call by reference« and
>  »call by name« using macros in C.

Call by name would be pretty hard just using macros. As far
as I know, you need actual callable functions to do it.

-- glen

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#43804

FromKaz Kylheku <kaz@kylheku.com>
Date2014-04-29 04:21 +0000
Message-ID<20140428211415.679@kylheku.com>
In reply to#43797
On 2014-04-29, Stefan Ram <ram@zedat.fu-berlin.de> wrote:
> Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
>>On the matter of terminology, I am not persuaded that simply passing a
>>pointer should be called pass by reference.  I realise that you won't be
>>persuaded, so we can just agree to differ.
>
>   It always refers to the /argument expression/. When the
>   argument value already is an address of an object o, as in
>
> f( &o )
>
>   , then pass-by-reference would require a reference to »&o«
>   (not to »o«), because the argument expression is »&o« and
>   not »o«. C only has pass-by-value in function calls. Also
>   in »f( &o )«, the /value/ of »&o« is passed.

We can easily talk, informally, about o being passed by reference (not &o, of course).

The variable o is the important value, and & is just a piece of "C fluff" to
get the called function to be able to update o.

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