Linux manual pages Section 3  

Name

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>
.TP
int strcasecmp( const char *s1,
  const char *s2);
  
Compare the strings
.I s1
and
.I s2
ignoring case.
.TP
int strncasecmp( const char *s1,
  const char *s2,
  size_t n);
  
Compare the first
.I n
bytes of the strings
.I s1
and
.I s2
ignoring case.
.TP
char *index( const char *s,
  int c);
  
Return a pointer to the first occurrence of the character
.I c
in the string
.IR s .
.TP
char *rindex( const char *s,
  int c);
  
Return a pointer to the last occurrence of the character
.I c
in the string
.IR s .
.TP
#include <string.h>
.TP
char *stpcpy( char *restrict dest,
  const char *restrict src);
  
Copy a string from
.I src
to
.IR dest ,
returning a pointer to the end of the resulting string at
.IR dest .
.TP
char *strcat( char *restrict dest,
  const char *restrict src);
  
Append the string
.I src
to the string
.IR dest ,
returning a pointer
.IR dest .
.TP
char *strchr( const char *s,
  int c);
  
Return a pointer to the first occurrence of the character
.I c
in the string
.IR s .
.TP
int strcmp( const char *s1,
  const char *s2);
  
Compare the strings
.I s1
with
.IR s2 .
.TP
int strcoll( const char *s1,
  const char *s2);
  
Compare the strings
.I s1
with
.I s2
using the current locale.
.TP
char *strcpy( char *restrict dest,
  const char *restrict src);
  
Copy the string
.I src
to
.IR dest ,
returning a pointer to the start of
.IR dest .
.TP
size_t strcspn( const char *s,
  const char *reject);
  
Calculate the length of the initial segment of the string
.I s
which does not contain any of bytes in the string
.IR reject ,
.TP
char *strdup( const char *s);
  
Return a duplicate of the string
.I s
in memory allocated using
.BR malloc (3).
.TP
char *strfry( char *string);
  
Randomly swap the characters in
.IR string .
.TP
size_t strlen( const char *s);
  
Return the length of the string
.IR s .
.TP
char *strncat( char *restrict dest,
  const char *restrict src,
  size_t n);
  
Append at most
.I n
bytes from the string
.I src
to the string
.IR dest ,
returning a pointer to
.IR dest .
.TP
int strncmp( const char *s1,
  const char *s2,
  size_t n);
  
Compare at most
.I n
bytes of the strings
.I s1
and
.IR s2 .
.TP
char *strncpy( char *restrict dest,
  const char *restrict src,
  size_t n);
  
Copy at most
.I n
bytes from string
.I src
to
.IR dest ,
returning a pointer to the start of
.IR dest .
.TP
char *strpbrk( const char *s,
  const char *accept);
  
Return a pointer to the first occurrence in the string
.I s
of one of the bytes in the string
.IR accept .
.TP
char *strrchr( const char *s,
  int c);
  
Return a pointer to the last occurrence of the character
.I c
in the string
.IR s .
.TP
char *strsep( char **restrict stringp,
  const char *restrict delim);
  
Extract the initial token in
.I stringp
that is delimited by one of the bytes in
.IR delim .
.TP
size_t strspn( const char *s,
  const char *accept);
  
Calculate the length of the starting segment in the string
.I s
that consists entirely of bytes in
.IR accept .
.TP
char *strstr( const char *haystack,
  const char *needle);
  
Find the first occurrence of the substring
.I needle
in the string
.IR haystack ,
returning a pointer to the found substring.
.TP
char *strtok( char *restrict s,
  const char *restrict delim);
  
Extract tokens from the string
.I s
that are delimited by one of the bytes in
.IR delim .
.TP
size_t strxfrm( char *restrict dst,
  const char *restrict src,
  size_t n);
  
Transforms
to the current locale and copies the first
bytes to

DESCRIPTION

The string functions perform operations on null-terminated strings. See the individual man pages for descriptions of each function.

SEE ALSO

bstring(3), 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

This page is part of release 5.11 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man−pages/.


  Copyright 1993 David Metcalfe (davidprism.demon.co.uk)

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References consulted:
    Linux libc source code
    Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
    386BSD man pages
Modified Sun Jul 25 10:54:31 1993, Rik Faith (faithcs.unc.edu)