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From: =?ISO-8859-2?Q?Daniel_Cegie=B3ka?= <daniel.cegielka@gmail.com>
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Subject: Re: REG_STARTEND (regex)
Date: Tue, 15 Jan 2013 19:55:23 +0100
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2013/1/15 Rich Felker <dalias@aerifal.cx>

> If the start position is 0, which it seems to be here, there's nothing
> to be done but removing REG_STARTEND. All it's doing is allowing you
> to process data with embedded nul bytes, which is not required by the
> standard or useful for any meaningful use of sed. Nobody will notice
> the difference with it missing unless they're trying to perform
> hideous hacks like patching binary files with sed...
>
> If the start position were not zero, you could compensate by just
> adding the start offset to the pointer you pass in, then adjusting all
> the match offsets after regexec returns.
>

thx Rich,
I found a similar solution in a 'file' package:

		else {
			regmatch_t pmatch[1];
#ifndef REG_STARTEND
#define	REG_STARTEND	0
			size_t l = ms->search.s_len - 1;
			char c = ms->search.s[l];
			((char *)(intptr_t)ms->search.s)[l] = '\0';
#else
			pmatch[0].rm_so = 0;
			pmatch[0].rm_eo = ms->search.s_len;
#endif
			rc = regexec(&rx, (const char *)ms->search.s,
			    1, pmatch, REG_STARTEND);
#if REG_STARTEND == 0
			((char *)(intptr_t)ms->search.s)[l] = c;
#endif
			switch (rc) {
			case 0:


https://raw.github.com/glensc/file/master/src/softmagic.c

Best regards,
Daniel