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udi_strcmp, udi_strncmp, udi_memcmp
String/memory comparison
#include <udi.h>udi_sbit8_t udi_strcmp ( const char *s1, const char *s2 ); udi_sbit8_t udi_strncmp ( const char *s1, const char *s2, udi_size_t n ); udi_sbit8_t udi_memcmp ( const void *s1, const void *s2, udi_size_t n );ARGUMENTS s1 is a pointer to the first character string or memory area.
s2 is a pointer to the second character string or memory area.
n is the maximum size to be compared (in bytes).
DESCRIPTION The udi_strcmp and udi_strncmp functions are used to compare the contents of two null-terminated character strings. The strings are compared on a byte-by-byte basis and a comparison value is returned when the first differing character or the end of the strings is reached.
For the udi_strncmp function, comparison halts after comparing n characters unless the end of either string has already been reached. If both strings are identical throughout the first n characters, the udi_strncmp function return value indicates that the strings are equal, regardless of any remaining content.
The udi_memcmp function operates in a similar manner as udi_strncmp except that null characters do not terminate the comparison, which will always continue until the specified n bytes have been compared or a difference has been reached.
RETURN VALUES These functions return an integer value less than, equal to, or greater than zero if s1 (or the first n bytes thereof) is lexicographically less than, equal, to, or greater than s2. This comparison is made by comparing each unsigned byte value until there is a mismatch or all bytes compare equal.