regex(3)           UNIX System V(BSD Compatibility Package)            regex(3)


NAME
      regex, recomp, reexec - regular expression handler

SYNOPSIS
      cc [ flag. . . ] file . . . -lucb

      char *recomp(s)
      char *s;

      reexec(s)
      char *s;

DESCRIPTION
      recomp compiles a string into an internal form suitable for pattern
      matching.  reexec checks the argument string against the last string
      passed to recomp.

      recomp returns a NULL pointer if the string s was compiled successfully;
      otherwise a string containing an error message is returned.  If recomp
      is passed 0 or a NULL string, it returns without changing the currently
      compiled regular expression.

      reexec returns 1 if the string s matches the last compiled regular
      expression, 0 if the string s failed to match the last compiled regular
      expression, and -1 if the compiled regular expression was invalid
      (indicating an internal error).

      The strings passed to both recomp and reexec may have trailing or
      embedded NEWLINE characters; they are terminated by NULL characters.  The
      regular expressions recognized are described in the manual page entry for
      ed(1), given the above difference.

SEE ALSO
      ed(1), ex(1), grep(1) in the User's Reference Manual
      regcmp(1), regexpr(3G), regcmp(3X), regexpr(5) in the Programmer's
      Reference Manual

RETURN VALUE
      reexec returns -1 for an internal error.

      recomp returns one of the following strings if an error occurs:

            No previous regular expression
            Regular expression too long
            unmatched \(
            missing ]
            too many \(\) pairs
            unmatched \)






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