svn commit: r317709 - head/usr.bin/csplit

[Bruce Evans]

On Tue, 2 May 2017, Jilles Tjoelker wrote:

> Log:
>  csplit: Fix check of fputs() return value, making csplit work again.
>
>  As of r295638, fputs() returns the number of bytes written (if not more than
>  INT_MAX). This broke csplit completely, since csplit assumed only success
>  only for the return value 0.
>
>  PR:		213510
>  Submitted by:	J.R. Oldroyd
>  MFC after:	1 week
>  Relnotes:	yes
>
> Modified:
>  head/usr.bin/csplit/csplit.c
>
> Modified: head/usr.bin/csplit/csplit.c
> ==============================================================================
> --- head/usr.bin/csplit/csplit.c	Tue May  2 21:33:27 2017	(r317708)
> +++ head/usr.bin/csplit/csplit.c	Tue May  2 21:56:20 2017	(r317709)
> @@ -195,7 +195,7 @@ main(int argc, char *argv[])
> 	/* Copy the rest into a new file. */
> 	if (!feof(infile)) {
> 		ofp = newfile();
> -		while ((p = get_line()) != NULL && fputs(p, ofp) == 0)
> +		while ((p = get_line()) != NULL && fputs(p, ofp) != EOF)
> 			;
> 		if (!sflag)
> 			printf("%jd\n", (intmax_t)ftello(ofp));

I don't like checking for the specific value EOF instead of any negative
value, though the EOF is Standard and I like checking for specific -1
for sysctls.  stdio is not very consistent, and this bug is due to old
versions of FreeBSD documenting and returning the specific value 0 on
non-error, which was also Standard.

Grepping for fputs in /usr/src shows too many instances to check (mostly
without any error handling).  The simplest filter 'if (fputs' found the
dependency on the old FreeBSD behaviour in csplit and 2 other places:

contrib/mdocml/main.c:		if (fputs(cp, stdout)) {
contrib/mdocml/main.c-			fclose(stream);
contrib/libreadline/examples/rlcat.c:	  if (fputs (x, stdout) != 0)
contrib/libreadline/examples/rlcat.c-	    return 1;

More complicated filters like 'if ([^(]]*[^a-z_]fputs' failed to find
any problems since I messed up the regexp.

mdocml is undocumented in its on man page, since that man page is a link
to mandoc(1) nad doesn't contain the word mdocml.

Bruce