regex problem

[Adam T. Bowen]

Hi,

        I am having some difficulty with the regex functions (regexec, 
regcomp) in libc version 2.2.93 compiling with gcc version 3.2.  The code 
is as follows :

#include <sys/types.h>
#include <regex.h>

int main(int argc, char **argv)
{
  regex_t RE;
  regmatch_t RM[10];
  char *Test_String="testing\n";
  int Pos=0;

  regcomp(&RE, "(t[^z]+z)",REG_EXTENDED);
  while(regexec(&RE, &Test_String[Pos], (size_t)1, RM, 0) == 0) 
  {
    printf("Match from %ld to %ld\n",Pos+RM[0].rm_so,Pos+RM[0].rm_eo-1);
    Pos+=RM[0].rm_eo;
  }
  return 0;
}

The output of this is :

        Match from 0 to 7

If the regular expression is changed to "(t[^r]+z)" 'r' being another
character that isn't in the string, it outputs nothing, as expected.  
Also, if I change the string to "testing" (the trailing newline removed)  
and use it with the original regular expression "(t[^z]+z)" it also
outputs nothing, as expected.  The same code using libc version 2.2.4
works correctly.  

        While I'm on, could I ask if anyone has any opinions of what is
better to use - as concerns speed, portability and development - gnu regex
functions or posix regex functions?

Thank you for your time.

Adam Bowen