REGEX(2,L)                  AIX Technical Reference                  REGEX(2,L)



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regex: re_comp, re_exec



PURPOSE

Handles regular expressions.

LIBRARY

Berkeley Compatibility Library (libbsd.a)

SYNTAX

char *re_comp (s)
char *s;

int *re_exec (s)
char *s;

DESCRIPTION

The re_comp subroutine complies a string into an internal form suitable for
pattern matching.  The re_exec subroutine checks the argument string against
the last string passed to re_comp.

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

The re_exec subroutine 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 the ed command, given the
above difference.

RETURN VALUE

If an error occurs, re_exec returns a -1, while re_comp returns one of the
following strings:

   No previous regular expression.
   Regular expression too long.
   Unmatched \(.
   Missing ]
   Too many \(\) pairs.



Processed November 7, 1990        REGEX(2,L)                                  1

REGEX(2,L)                  AIX Technical Reference                  REGEX(2,L)



   Unmatched \).

RELATED INFORMATION

In this book:  "NCcollate, NCcoluniq, NCeqvmap, _NCxcol, _NLxcol," "regcmp,
regex," and "regexp: compile, step, advance."

The ed, grep, and sed commands in AIX Operating System Commands Reference.

"Introduction to International Character Support" in Managing the AIX Operating
System.












































Processed November 7, 1990        REGEX(2,L)                                  2