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/*
FUNCTION
<<strstr>>---find string segment
INDEX
strstr
ANSI_SYNOPSIS
#include <string.h>
char *strstr(const char *<[s1]>, const char *<[s2]>);
TRAD_SYNOPSIS
#include <string.h>
char *strstr(<[s1]>, <[s2]>)
char *<[s1]>;
char *<[s2]>;
DESCRIPTION
Locates the first occurence in the string pointed to by <[s1]> of
the sequence of characters in the string pointed to by <[s2]>
(excluding the terminating null character).
RETURNS
Returns a pointer to the located string segment, or a null
pointer if the string <[s2]> is not found. If <[s2]> points to
a string with zero length, the <[s1]> is returned.
PORTABILITY
<<strstr>> is ANSI C.
<<strstr>> requires no supporting OS subroutines.
QUICKREF
strstr ansi pure
*/
#include <string.h>
char *
_DEFUN (strstr, (searchee, lookfor),
_CONST char *searchee _AND
_CONST char *lookfor)
{
if (*searchee == 0)
{
if (*lookfor)
return (char *) NULL;
return (char *) searchee;
}
while (*searchee)
{
size_t i;
i = 0;
while (1)
{
if (lookfor[i] == 0)
{
return (char *) searchee;
}
if (lookfor[i] != searchee[i])
{
break;
}
i++;
}
searchee++;
}
return (char *) NULL;
}
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