Re: grep: fix multibyte regex handling under macOS (1819ad327b7a1f19540a819813b70a0e8a7f798f)

On Thu, Feb 02, 2023 at 03:47:28PM -0500, D. Ben Knoble wrote:

Further, the following C program compiles without warnings (except for
the unused main parameters):

#include <regex.h>
#include <assert.h>
#include <stddef.h>
#include <stdio.h>

int main(int argc, char **argv) {
    regex_t re;
    int ret = regcomp(&re, "[\xc0-\xff][\x80-\xbf]+", REG_EXTENDED |
REG_NEWLINE);
    /* assert(ret != 0); */
    size_t errbuf_size = regerror(ret, &re, NULL, 0);
    char errbuf[errbuf_size];
    regerror(ret, &re, errbuf, errbuf_size);
    printf("%s\n", errbuf);
}

Just a guess, but does calling:

  setlocale(LC_CTYPE, "");

at the start of the program change things (you'll probably need to also
include locale.h)? I don't have a macos system to test on.

-Peff