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/*
* strstr.c -- return the offset of one string within another.
*
* Copyright (C) 1997 Free Software Foundation, Inc.
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2, or (at your option) any later
* version.
*
* This program 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 General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* Written by Philippe De Muyter <phdm@info.ucl.ac.be>. */
/*
* NAME
*
* strstr -- locate first occurence of a substring
*
* SYNOPSIS
*
* char *strstr (char *s1, char *s2)
*
* DESCRIPTION
*
* Locates the first occurence in the string pointed to by S1 of the string
* pointed to by S2. Returns a pointer to the substring found, or a NULL
* pointer if not found. If S2 points to a string with zero length, the
* function returns S1.
*
* BUGS
*
*/
char *
strstr (buf, sub)
register char *buf;
register char *sub;
{
register char *bp;
if (!*sub)
return buf;
for (;;)
{
if (!*buf)
break;
bp = buf;
for (;;)
{
if (!*sub)
return buf;
if (*bp++ != *sub++)
break;
}
sub -= (unsigned long) bp;
sub += (unsigned long) buf;
buf += 1;
}
return 0;
}
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