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STRSTR(3)             DragonFly Library Functions Manual             STRSTR(3)


strstr, strcasestr, strnstr -- locate a substring in a string


Standard C Library (libc, -lc)


#include <string.h> char * strstr(const char *big, const char *little); char * strcasestr(const char *big, const char *little); char * strnstr(const char *big, const char *little, size_t len); #include <string.h> #include <xlocale.h> char * strcasestr_l(const char *big, const char *little, locale_t loc);


The strstr() function locates the first occurrence of the null-terminated string little in the null-terminated string big. The strcasestr() function is similar to strstr(), but ignores the case of both strings. The strcasestr_l() function does the same as strcasestr() but takes an explicit locale rather than using the current locale. The strnstr() function locates the first occurrence of the null- terminated string little in the string big, where not more than len characters are searched. Characters that appear after a `\0' character are not searched. Since the strnstr() function is a FreeBSD specific API, it should only be used when portability is not a concern.


If little is an empty string, big is returned; if little occurs nowhere in big, NULL is returned; otherwise a pointer to the first character of the first occurrence of little is returned.


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);


memchr(3), memmem(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strtok(3), wcsstr(3)


The strstr() function conforms to ISO/IEC 9899:1990 (``ISO C90''). DragonFly 3.5 October 11, 2001 DragonFly 3.5

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