NAME | SYNOPSIS | DESCRIPTION | ATTRIBUTES
#include <string.h>int * strcasecmp(const char * s1, const char * s2);
The s1 , s2 and s arguments point to strings (arrays of characters terminated by a null character). The strcat , strncat , strcpy and strncpy functions all alter s1. These functions do not check for overflow of the array pointed to by s1 .
The strcasecmp and strncasecmp functions compare the null-terminated strings s1 and s2 and return an integer greater than, equal to, or less than 0, according to whether s1 is lexicographically greater than, equal to, or less than s2 (after translation of each corresponding character to lower-case). The strings themselves are not modified. The comparison is done using unsigned characters, meaning that 200 is greater than 0 .
The strncasecmp compares a maximum of n characters.
The strcat and strncat functions append a copy of string s2 to the end of string s1 . The strncat function copies only the first n bytes of s2 . Each returns a pointer to the null-terminated result.
The strcmp function compares its arguments and returns an integer less than, equal to, or greater than 0, according to whether s1 is lexicographically less than, equal to, or greater than s2 .
If insufficient memory is available, NULL is returned. The strncmp function makes the same comparison, but looks at a maximum of n characters.
The strcoll function lexicographically compares the null-terminated strings s1 and s2 according to the current locale collation and returns an integer greater than, equal to, or less than 0, according to whether s1 is greater than, equal to, or less than s2 .
The strdup function allocates sufficient memory for a copy of the string s , does the copy, and returns a pointer to it. The pointer may subsequently be used as an argument to the function free(3STDC).
The strcpy function copies string s2 to s1 , stopping after the null character has been copied. strncpy copies exactly n characters, truncating s2 or adding null characters to s1 if necessary. The result will not be null-terminated if the length of s2 is n or more. Each function returns s1 .
The strlen function returns the number of characters in s , not including the terminating null character.
The strchr and strrchr functions return a pointer to the first or last)cccurrence of character c in string s , respectively,. If c does not occur in the string, a NULL pointer is returned. The null character terminating a string is considered to be part of the string.
The strpbrk function returns a pointer to the first occurrence in string s1 of any character from string s2 , or a NULL pointer if no character from s2 exists in s1 .
The strspn and strcspn functions return the length of the initial segment of string s1 which consists entirely of characters from or to string s2 , respectively.
The strstr function locates the first occurence of the null-terminated string s2 in the null-terminated string s1 . If s2 is the empty string, strstr returns s1 ; if s2 occurs nowhere in s1 , strstr returns NULL , otherwise strstr returns a pointer to the first character of the first occurrence of s2 .
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
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Interface Stability | Evolving |
NAME | SYNOPSIS | DESCRIPTION | ATTRIBUTES