STRCASECMP(3) BSD Library Functions Manual STRCASECMP(3)NAME
strcasecmp, strncasecmp — compare strings, ignoring case
Standard C Library (libc, -lc)
strcasecmp(const char *s1, const char *s2);
strncasecmp(const char *s1, const char *s2, size_t len);
The strcasecmp() and strncasecmp() functions compare the null-terminated
strings s1 and s2.
The strncasecmp() compares at most len characters.
The strcasecmp() and strncasecmp() return an integer greater than, equal
to, or less than 0, according as s1 is lexicographically greater than,
equal to, or less than s2 after translation of each corresponding charac‐
ter to lower-case. The strings themselves are not modified. The compar‐
ison is done using unsigned characters, so that ‘\200’ is greater than
SEE ALSObcmp(3), memcmp(3), strcmp(3), strcoll(3), strxfrm(3), tolower(3),
The strcasecmp() and strncasecmp() functions first appeared in 4.4BSD.
Their prototypes existed previously in <string.h> before they were moved
to <strings.h> for IEEE Std 1003.1-2001 (“POSIX.1”) compliance.
BSD June 9, 1993 BSD