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Man Pages › Section 3

string(3)

stpcpy, strcasecmp, strcat, strchr, strcmp, strcoll, strcpy, strcspn, strdup, strfry, strlen, strncat, strncmp, strncpy, strncasecmp, strpbrk, strrchr, strsep, strspn, strstr, strtok, strxfrm, index, rindex – string operations

Synopsis

#include <strings.h>

int strcasecmp(const char *s1, const char *s2);


Compare the strings
s1


    and
        s2

            ignoring case.int
            strncasecmp(const char *s1, const char *s2, size_t n);

Compare the first
n
    bytes of the strings
        s1

            and
                s2

                    ignoring case.char *
                    index(const char *s, int c);

Return a pointer to the first occurrence of the character
c
    in the string
        s.

char *
rindex(const char *s, int c);

Return a pointer to the last occurrence of the character
c
    in the string
        s.

#include <string.h>
char *
stpcpy(char *dest, const char *src);

Copy a string from
src
    to
        dest,

returning a pointer to the end of the resulting string at
    dest.

char *
strcat(char *dest, const char *src);

Append the string
src
    to the string
        dest,

returning a pointer
    dest.

char *
strchr(const char *s, int c);

Return a pointer to the first occurrence of the character
c
    in the string
        s.

int
strcmp(const char *s1, const char *s2);

Compare the strings
s1
    with
        s2.

int
strcoll(const char *s1, const char *s2);

Compare the strings
s1
    with
        s2

using the current locale.char *
strcpy(char *dest, const char *src);

Copy the string
src
    to
        dest,

returning a pointer to the start of
    dest.

size_t
strcspn(const char *s, const char *reject);

Calculate the length of the initial segment of the string
s
    which does not contain any of bytes in the string
        reject,

char *strdup(const char *s);

Return a duplicate of the string
s
    in memory allocated using malloc(3)
        .

char *strfry(char *string);

Randomly swap the characters in
string.
size_t
strlen(const char *s);

Return the length of the string
s.
char *
strncat(char *dest, const char *src, size_t n);

Append at most
n
    bytes from the string
        src

            to the string
                dest,

returning a pointer to
    dest.

int
strncmp(const char *s1, const char *s2, size_t n);

Compare at most
n
    bytes of the strings
        s1

            and
                s2.

char *
strncpy(char *dest, const char *src, size_t n);

Copy at most
n
    bytes from string
        src

            to
                dest,

returning a pointer to the start of
    dest.

char *
strpbrk(const char *s, const char *accept);

Return a pointer to the first occurrence in the string
s
    of one of the bytes in the string
        accept.

char *
strrchr(const char *s, int c);

Return a pointer to the last occurrence of the character
c
    in the string
        s.

char *
strsep(char **stringp, const char *delim);

Extract the initial token in
stringp
    that is delimited by one of the bytes in
        delim.

size_t
strspn(const char *s, const char *accept);

Calculate the length of the starting segment in the string
s
    that consists entirely of bytes in
        accept.

char *
strstr(const char *haystack, const char *needle);

Find the first occurrence of the substring
needle
    in the string
        haystack,

returning a pointer to the found substring.char *strtok(char *s, const char *delim);

Extract tokens from the string
s
    that are delimited by one of the bytes in
        delim.

size_t
strxfrm(char *dest, const char *src, size_t n);

Transforms
src
    to the current locale and copies the first
        n

            bytes to
                dest.</code></pre>

Description
The string functions perform operations on null-terminated strings. See the individual man pages for descriptions of each function.
See Also
index(3), rindex(3), stpcpy(3), strcasecmp(3), strcat(3), strchr(3), strcmp(3), strcoll(3), strcpy(3), strcspn(3), strdup(3), strfry(3), strlen(3), strncasecmp(3), strncat(3), strncmp(3), strncpy(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strstr(3), strtok(3), strxfrm(3)
Colophon
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