Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.c > #10825

Re: evaluate a generic swap function

Show all headers | View raw

Nelu wrote:
 
> Yes, but memory for the tmp variable in your example is allocated/deallocated every time you enter/exit the block of code. The static variable is allocated at the start of the program and successive calls to the function will not need to allocate more memory. Same with the thread local variables as long as you reuse the same threads, no?

If you want instead, to have a single memory reservation
for multiple function calls, and also to have thread safety,
then you could copy the technique used for the renentrant
varieties of strtok, commonly available on many systems
and usually known as either strtok_r or strtokr.
You add another parameter to the swap function 
with the address of the scratch memory.  
The scratch memory is reserved in the calling function
and can have any kind of duration.

-- 
pete

Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

evaluate a generic swap function Stanley Rice <heconghui@gmail.com> - 2011-09-20 06:51 -0700
  Re: evaluate a generic swap function jacob navia <jacob@spamsink.net> - 2011-09-20 16:01 +0200
    Re: evaluate a generic swap function jt@toerring.de (Jens Thoms Toerring) - 2011-09-20 14:29 +0000
      Re: evaluate a generic swap function jacob navia <jacob@spamsink.net> - 2011-09-20 21:13 +0200
        Re: evaluate a generic swap function jt@toerring.de (Jens Thoms Toerring) - 2011-09-20 20:30 +0000
          Re: evaluate a generic swap function Keith Thompson <kst-u@mib.org> - 2011-09-20 17:05 -0700
            Re: evaluate a generic swap function gazelle@shell.xmission.com (Kenny McCormack) - 2011-09-21 15:45 +0000
              Re: evaluate a generic swap function Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-09-21 09:33 -0700
              Re: evaluate a generic swap function jacob navia <jacob@spamsink.net> - 2011-09-21 19:17 +0200
                Re: evaluate a generic swap function gazelle@shell.xmission.com (Kenny McCormack) - 2011-09-21 17:34 +0000
                Re: evaluate a generic swap function Jack Foot <foot@dev.null.invalid> - 2011-09-21 18:12 +0000
  Re: evaluate a generic swap function Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-09-20 07:33 -0700
    Re: evaluate a generic swap function ImpalerCore <jadill33@gmail.com> - 2011-09-20 08:26 -0700
      Re: evaluate a generic swap function pete <pfiland@mindspring.com> - 2011-09-20 23:10 -0400
  Re: evaluate a generic swap function "BartC" <bc@freeuk.com> - 2011-09-20 22:20 +0100
    Re: evaluate a generic swap function jacob navia <jacob@spamsink.net> - 2011-09-20 23:23 +0200
      Re: evaluate a generic swap function Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-20 23:07 +0100
  Re: evaluate a generic swap function Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-20 21:15 -0400
    Re: evaluate a generic swap function Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-09-21 03:17 -0700
  Re: evaluate a generic swap function Gene <gene.ressler@gmail.com> - 2011-09-21 02:40 -0700
  Re: evaluate a generic swap function Seebs <usenet-nospam@seebs.net> - 2011-09-23 01:46 +0000
    Re: evaluate a generic swap function Nelu <tandauioan@gmail.com> - 2011-09-23 10:26 -0700
      Re: evaluate a generic swap function Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-23 18:36 +0100
        Re: evaluate a generic swap function Nelu <tandauioan@gmail.com> - 2011-09-23 10:49 -0700
          Re: evaluate a generic swap function Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-23 20:18 +0100
            Re: evaluate a generic swap function Nelu <tandauioan@gmail.com> - 2011-09-23 12:54 -0700
              Re: evaluate a generic swap function James Kuyper <jameskuyper@verizon.net> - 2011-09-23 16:43 -0400
                Re: evaluate a generic swap function Nelu <tandauioan@gmail.com> - 2011-09-23 13:49 -0700
                Re: evaluate a generic swap function James Kuyper <jameskuyper@verizon.net> - 2011-09-23 17:44 -0400
                Re: evaluate a generic swap function Nelu <tandauioan@gmail.com> - 2011-09-23 18:04 -0700
                Re: evaluate a generic swap function Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-24 13:52 -0800
              Re: evaluate a generic swap function Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-23 21:46 +0100
                Re: evaluate a generic swap function Nelu <tandauioan@gmail.com> - 2011-09-23 13:59 -0700
                Re: evaluate a generic swap function Seebs <usenet-nospam@seebs.net> - 2011-09-26 22:59 +0000
          Re: evaluate a generic swap function pete <pfiland@mindspring.com> - 2011-09-23 18:19 -0400
            Re: evaluate a generic swap function Nelu <tandauioan@gmail.com> - 2011-09-23 16:36 -0700

csiph-web