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strstr(3) [centos man page]

STRSTR(3)						     Linux Programmer's Manual							 STRSTR(3)

strstr, strcasestr - locate a substring SYNOPSIS
#include <string.h> char *strstr(const char *haystack, const char *needle); #define _GNU_SOURCE /* See feature_test_macros(7) */ #include <string.h> char *strcasestr(const char *haystack, const char *needle); DESCRIPTION
The strstr() function finds the first occurrence of the substring needle in the string haystack. The terminating null bytes ('') are not compared. The strcasestr() function is like strstr(), but ignores the case of both arguments. RETURN VALUE
These functions return a pointer to the beginning of the substring, or NULL if the substring is not found. CONFORMING TO
The strstr() function conforms to C89 and C99. The strcasestr() function is a nonstandard extension. BUGS
Early versions of Linux libc (like 4.5.26) would not allow an empty needle argument for strstr(). Later versions (like 4.6.27) work cor- rectly, and return haystack when needle is empty. SEE ALSO
index(3), memchr(3), rindex(3), strcasecmp(3), strchr(3), string(3), strpbrk(3), strsep(3), strspn(3), strtok(3), wcsstr(3) COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at GNU
2011-09-28 STRSTR(3)

Check Out this Related Man Page

STRSTR(3)						   BSD Library Functions Manual 						 STRSTR(3)

strstr, strcasestr, strnstr -- locate a substring in a string LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <string.h> char * strstr(const char *haystack, const char *needle); char * strcasestr(const char *haystack, const char *needle); char * strnstr(const char *haystack, const char *needle, size_t len); #include <string.h> #include <xlocale.h> char * strcasestr_l(const char *haystack, const char *needle, locale_t loc); DESCRIPTION
The strstr() function locates the first occurrence of the null-terminated string needle in the null-terminated string haystack. The strcasestr() function is similar to strstr(), but ignores the case of both strings. The strnstr() function locates the first occurrence of the null-terminated string needle in the string haystack, where not more than len characters are searched. Characters that appear after a '' character are not searched. Since the strnstr() function is a FreeBSD specific API, it should only be used when portability is not a concern. While the strcasestr() function uses the current locale, the strcasestr_l() function may be passed a locale directly. See xlocale(3) for more information. RETURN VALUES
If needle is an empty string, haystack is returned; if needle occurs nowhere in haystack, NULL is returned; otherwise a pointer to the first character of the first occurrence of needle is returned. EXAMPLES
The following sets the pointer ptr to the "Bar Baz" portion of largestring: const char *largestring = "Foo Bar Baz"; const char *smallstring = "Bar"; char *ptr; ptr = strstr(largestring, smallstring); The following sets the pointer ptr to NULL, because only the first 4 characters of largestring are searched: const char *largestring = "Foo Bar Baz"; const char *smallstring = "Bar"; char *ptr; ptr = strnstr(largestring, smallstring, 4); SEE ALSO
memchr(3), memmem(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strtok(3), wcsstr(3), xlocale(3) STANDARDS
The strstr() function conforms to ISO/IEC 9899:1990 (``ISO C90''). BSD
October 11, 2001 BSD

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