Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
| From | James Harris <james.harris.1@gmail.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: When parameters to printf are in memory |
| Date | 2016-10-04 08:32 +0100 |
| Organization | A noiseless patient Spider |
| Message-ID | <nsvltk$4ja$1@dont-email.me> (permalink) |
| References | (7 earlier) <nsk3ic$kh3$1@dont-email.me> <nsmcbv$2cc$1@dont-email.me> <87r3816u6r.fsf@bsb.me.uk> <nsnqsn$lsj$1@dont-email.me> <nso2bv$b6j$1@dont-email.me> |
On 01/10/2016 11:15, BartC wrote:
> On 01/10/2016 09:08, James Harris wrote:
>
>> I started down this road basically thinking to use snprintf as an easy
>> way to plug rendered values into an error message. After all, it's built
>> for just such an operation. And it is usually easier to use a built-in
>> facility than writing one from scratch.
>
>
> I think using the a printf-style format string, while it may be
> attractive and familiar, is causing issues.
>
> Perhaps use a different approach. For example, start with what you had:
>
> struct {
> char *text; // "Error on line %04d in file \"%s\"\n"
> union any parms[]; // ({int}428, {char*}"file.c")
> };
>
> The {int} etc indicate the implied type of the value in each union.
>
> Now move the detailed formats to the unions (effectively, tag each union
> with the type of its value):
>
> struct {
> char *text; // "Error on line # in file \"#\"\n"
> union any parms[]; // (("%04d",428), ("%s","file.c"))
> };
Good idea. That seems more flexible overall, not just for this
application. And it harks back to something we discussed before -
separating knowledge of types from printing. Then the system-provided
print routines don't have to know about all printable object types.
--
James Harris
Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-09-29 16:20 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-09-29 16:43 +0100
Re: When parameters to printf are in memory Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-09-29 20:30 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-09-29 21:23 +0100
Re: When parameters to printf are in memory BartC <bc@freeuk.com> - 2016-09-29 22:03 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-09-29 22:35 +0100
Re: When parameters to printf are in memory BartC <bc@freeuk.com> - 2016-09-29 23:11 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-09-30 19:53 +0100
Re: When parameters to printf are in memory Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-09-30 20:53 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-01 09:08 +0100
Re: When parameters to printf are in memory BartC <bc@freeuk.com> - 2016-10-01 11:15 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-04 08:32 +0100
Re: When parameters to printf are in memory Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-01 11:15 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-04 08:28 +0100
Re: When parameters to printf are in memory Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-04 09:49 +0100
Re: When parameters to printf are in memory BartC <bc@freeuk.com> - 2016-10-04 11:43 +0100
Re: When parameters to printf are in memory Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-04 13:42 +0100
Re: When parameters to printf are in memory BartC <bc@freeuk.com> - 2016-10-04 14:03 +0100
Re: When parameters to printf are in memory Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-04 14:16 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-04 20:01 +0100
Re: When parameters to printf are in memory Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-04 20:24 +0100
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-04 20:40 +0100
Re: When parameters to printf are in memory Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-04 22:51 +0100
Re: When parameters to printf are in memory "James R. Kuyper" <jameskuyper@verizon.net> - 2016-10-04 14:25 -0400
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-04 20:31 +0100
Re: When parameters to printf are in memory BartC <bc@freeuk.com> - 2016-09-29 17:03 +0100
Re: When parameters to printf are in memory gazelle@shell.xmission.com (Kenny McCormack) - 2016-09-30 12:20 +0000
Re: When parameters to printf are in memory Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-09-30 05:55 -0700
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-09-30 20:06 +0100
Re: When parameters to printf are in memory gazelle@shell.xmission.com (Kenny McCormack) - 2016-09-30 22:01 +0000
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-01 09:15 +0100
Re: When parameters to printf are in memory Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-09-30 23:18 -0700
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-01 09:32 +0100
Re: When parameters to printf are in memory jacobnavia <jacob@jacob.remcomp.fr> - 2016-09-29 18:35 +0200
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-09-29 19:55 +0100
Re: When parameters to printf are in memory jacobnavia <jacob@jacob.remcomp.fr> - 2016-09-29 21:22 +0200
Re: When parameters to printf are in memory Barry Schwarz <schwarzb@dqel.com> - 2016-09-29 11:20 -0700
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-09-29 20:08 +0100
Re: When parameters to printf are in memory Lőrinczy Zsigmond <nospam@for.me> - 2016-10-02 20:15 +0200
Re: When parameters to printf are in memory Lőrinczy Zsigmond <nospam@for.me> - 2016-10-02 20:19 +0200
Re: When parameters to printf are in memory gazelle@shell.xmission.com (Kenny McCormack) - 2016-10-02 18:29 +0000
Re: When parameters to printf are in memory Lőrinczy Zsigmond <nospam@for.me> - 2016-10-03 07:04 +0200
Re: When parameters to printf are in memory James Harris <james.harris.1@gmail.com> - 2016-10-04 08:36 +0100
Re: When parameters to printf are in memory jacobnavia <jacob@jacob.remcomp.fr> - 2016-10-02 21:27 +0200
csiph-web