STRCAT(10.2) STRCAT(10.2) NAME strcat, strcmp, strncmp, strcpy, strncpy, strlen, strchr, strrchr, strdup, strstr - string operations SYNOPSIS char* strcat(char *s1, char *s2) int strcmp(char *s1, char *s2) int strncmp(char *s1, char *s2, long n) char* strcpy(char *s1, char *s2) char* strncpy(char *s1, char *s2, long n) long strlen(char *s) char* strchr(char *s, char c) char* strrchr(char *s, char c) char* strdup(char *s) char* strstr(char *s1, char *s2) DESCRIPTION The arguments s1, s2 and s point to null-terminated strings. The functions strcat, strcpy, and strncpy all alter s1. These functions do not check for overflow of the array pointed to by s1. Strcat appends a copy of string s2 to the end of string s1, and returns a pointer to the null-terminated result. Strcmp compares its arguments and returns an integer less than, equal to, or greater than 0, according as s1 is lexi- cographically less than, equal to, or greater than s2. Strncmp makes the same comparison but examines at most n bytes. The comparisons are made with unsigned bytes. Strcpy copies string s2 to s1, stopping after the null byte has been copied. Strncpy copies exactly n bytes, truncating s2 or adding null bytes to s1 if necessary. The result will not be null-terminated if the length of s2 is n or more. Each function returns s1. Strlen returns the number of bytes in s, not including the terminating null byte. Strchr (strrchr) returns a pointer to the first (last) STRCAT(10.2) STRCAT(10.2) occurrence of byte c in string s, or `0' if c does not occur in the string. The null byte terminating a string is con- sidered to be part of the string. Strdup returns a pointer to a distinct copy of the null- terminated string s in space obtained from malloc(10.2) or `0' if no space can be obtained. Strstr returns a pointer to the first occurrence of s2 as a substring of s1, or 0 if there is none. If s2 is the null string, strstr returns s1. SOURCE /libkern/str*.c /libkern/str*-objtype.c /lib9/strdup.c SEE ALSO memory(10.2), rune(10.2) BUGS These routines know nothing about UTF. Use the routines in rune(10.2) as appropriate. Note, however, that the defini- tion of UTF guarantees that strcmp compares UTF strings cor- rectly. The outcome of overlapping moves varies among implementa- tions. Note the absence of ANSI C's strncat, strpbrk, strspn, strcspn and strtok, but the presence of strdup.