4.3BSD - /usr/man/cat3/re_exec.0

REGEX(3)                                                              REGEX(3)


NAME
       re_comp, re_exec - regular expression handler

SYNOPSIS
       char *re_comp(s)
       char *s;

       re_exec(s)
       char *s;

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

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

       Re_exec 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 re_comp and re_exec may have trailing or
       embedded newline characters; they are terminated by nulls.  The regular
       expressions  recognized  are  described  in the manual entry for ed(1),
       given the above difference.

SEE ALSO
       ed(1), ex(1), egrep(1), fgrep(1), grep(1)

DIAGNOSTICS
       Re_exec returns -1 for an internal error.

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

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


3rd Berkeley Distribution        May 15, 1985                         REGEX(3)