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/* Simple implementation of strstr for systems without it.
This function is in the public domain. */
/*
@deftypefn Supplemental char* strstr (const char *@var{string}, const char *@var{sub})
This function searches for the substring @var{sub} in the string
@var{string}, not including the terminating null characters. A pointer
to the first occurrence of @var{sub} is returned, or @code{NULL} if the
substring is absent. If @var{sub} points to a string with zero
length, the function returns @var{string}.
@end deftypefn
*/
/* FIXME: The above description is ANSI compiliant. This routine has not
been validated to comply with it. -fnf */
char *
strstr (char *s1, char *s2)
{
register char *p = s1;
extern char *strchr ();
extern int strncmp ();
#if __GNUC__ >= 2
extern __SIZE_TYPE__ strlen (const char *);
#endif
register int len = strlen (s2);
for (; (p = strchr (p, *s2)) != 0; p++)
{
if (strncmp (p, s2, len) == 0)
{
return (p);
}
}
return (0);
}
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