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Edit File: regexp.h

/* Copyright (C) 1996-2021 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.

The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#ifndef _REGEXP_H
#define _REGEXP_H	1

/* The contents of this header file were originally standardized in
   the Single Unix Specification, Issue 3 (1992).  In Issue 4 (1994)
   the header was marked as TO BE WITHDRAWN, and new applications
   were encouraged to use <regex.h> instead.  It was officially
   withdrawn from the standard in Issue 6 (aka POSIX.1-2001).

The GNU C Library provided this header through version 2.22. */

#error "The GNU C Library no longer implements <regexp.h>."
#error "Please update your code to use <regex.h> instead (no trailing 'p')."

#endif /* regexp.h */