man strcasecmp () - case-insensitive string comparisons
NAME
strcasecmp, strncasecmp - case-insensitive string comparisons
SYNOPSIS
#include <strings.h>
int strcasecmp(const char *s1, const char *s2);
int strncasecmp(const char *s1, const char *s2,
size_t n);
DESCRIPTION
The strcasecmp() function shall compare, while ignoring differences in case, the string pointed to by s1 to the string pointed to by s2. The strncasecmp() function shall compare, while ignoring differences in case, not more than n bytes from the string pointed to by s1 to the string pointed to by s2.
In the POSIX locale, strcasecmp() and strncasecmp() shall behave as if the strings had been converted to lowercase and then a byte comparison performed. The results are unspecified in other locales.
RETURN VALUE
Upon completion, strcasecmp() shall return an integer greater than, equal to, or less than 0, if the string pointed to by s1 is, ignoring case, greater than, equal to, or less than the string pointed to by s2, respectively.
Upon successful completion, strncasecmp() shall return an integer greater than, equal to, or less than 0, if the possibly null-terminated array pointed to by s1 is, ignoring case, greater than, equal to, or less than the possibly null-terminated array pointed to by s2, respectively.
ERRORS
No errors are defined.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
The Base Definitions volume of IEEE Std 1003.1-2001, <strings.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .