/* * strncmp - compare at most n characters of string s1 to s2 */ #include "config.h" int /* <0 for <, 0 for ==, >0 for > */ strncmp(s1, s2, n) CONST char *s1; CONST char *s2; SIZET n; { register CONST char *scan1; register CONST char *scan2; register SIZET count; scan1 = s1; scan2 = s2; count = n; while (--count >= 0 && *scan1 != '\0' && *scan1 == *scan2) { scan1++; scan2++; } if (count < 0) return(0); /* * The following case analysis is necessary so that characters * which look negative collate low against normal characters but * high against the end-of-string NUL. */ if (*scan1 == '\0' && *scan2 == '\0') return(0); else if (*scan1 == '\0') return(-1); else if (*scan2 == '\0') return(1); else return(*scan1 - *scan2); }