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string.h(0p) — Linux manual page

PROLOG | NAME | SYNOPSIS | DESCRIPTION | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT 

string.h(0P)            POSIX Programmer's Manual            string.h(0P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The
       Linux implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       string.h — string operations

SYNOPSIS         top

       #include <string.h>

DESCRIPTION         top

       Some of the functionality described on this reference page extends
       the ISO C standard. Applications shall define the appropriate
       feature test macro (see the System Interfaces volume of
       POSIX.1‐2017, Section 2.2, The Compilation Environment) to enable
       the visibility of these symbols in this header.

       The <string.h> header shall define NULL and size_t as described in
       <stddef.h>.

       The <string.h> header shall define the locale_t type as described
       in <locale.h>.

       The following shall be declared as functions and may also be
       defined as macros. Function prototypes shall be provided for use
       with ISO C standard compilers.

           void    *memccpy(void *restrict, const void *restrict, int, size_t);
           void    *memchr(const void *, int, size_t);
           int      memcmp(const void *, const void *, size_t);
           void    *memcpy(void *restrict, const void *restrict, size_t);
           void    *memmove(void *, const void *, size_t);
           void    *memset(void *, int, size_t);
           char    *stpcpy(char *restrict, const char *restrict);
           char    *stpncpy(char *restrict, const char *restrict, size_t);
           char    *strcat(char *restrict, const char *restrict);
           char    *strchr(const char *, int);
           int      strcmp(const char *, const char *);
           int      strcoll(const char *, const char *);
           int      strcoll_l(const char *, const char *, locale_t);
           char    *strcpy(char *restrict, const char *restrict);
           size_t   strcspn(const char *, const char *);
           char    *strdup(const char *);
           char    *strerror(int);
           char    *strerror_l(int, locale_t);
           int      strerror_r(int, char *, size_t);
           size_t   strlen(const char *);
           char    *strncat(char *restrict, const char *restrict, size_t);
           int      strncmp(const char *, const char *, size_t);
           char    *strncpy(char *restrict, const char *restrict, size_t);
           char    *strndup(const char *, size_t);
           size_t   strnlen(const char *, size_t);
           char    *strpbrk(const char *, const char *);
           char    *strrchr(const char *, int);
           char    *strsignal(int);
           size_t   strspn(const char *, const char *);
           char    *strstr(const char *, const char *);
           char    *strtok(char *restrict, const char *restrict);
           char    *strtok_r(char *restrict, const char *restrict, char **restrict);
           size_t   strxfrm(char *restrict, const char *restrict, size_t);
           size_t   strxfrm_l(char *restrict, const char *restrict,
                        size_t, locale_t);

       Inclusion of the <string.h> header may also make visible all
       symbols from <stddef.h>.

       The following sections are informative.

APPLICATION USAGE         top

       None.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       locale.h(0p), stddef.h(0p), sys_types.h(0p)

       The System Interfaces volume of POSIX.1‐2017, Section 2.2, The
       Compilation Environment, memccpy(3p), memchr(3p), memcmp(3p),
       memcpy(3p), memmove(3p), memset(3p), strcat(3p), strchr(3p),
       strcmp(3p), strcoll(3p), strcpy(3p), strcspn(3p), strdup(3p),
       strerror(3p), strlen(3p), strncat(3p), strncmp(3p), strncpy(3p),
       strpbrk(3p), strrchr(3p), strsignal(3p), strspn(3p), strstr(3p),
       strtok(3p), strxfrm(3p)

COPYRIGHT         top

       Portions  of  this text are reprinted and reproduced in electronic
       form  from  IEEE  Std  1003.1-2017,   Standard   for   Information
       Technology  --  Portable  Operating  System Interface (POSIX), The
       Open Group Base Specifications Issue 7,  2018  Edition,  Copyright
       (C) 2018 by the Institute of Electrical and Electronics Engineers,
       Inc  and  The Open Group.  In the event of any discrepancy between
       this version and the original IEEE and The  Open  Group  Standard,
       the  original  IEEE  and  The  Open  Group Standard is the referee
       document.  The  original  Standard  can  be  obtained  online   at
       http://www.opengroup.org/unix/online.html .

       Any  typographical  or  formatting errors that appear in this page
       are most likely to have been introduced during the  conversion  of
       the  source  files  to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                2017                      string.h(0P)

Pages that refer to this page: wchar.h(0p),  wctype.h(0p),  memccpy(3p),  memchr(3p),  memcmp(3p),  memcpy(3p),  memmove(3p),  memset(3p),  strcat(3p),  strchr(3p),  strcmp(3p),  strcoll(3p),  strcpy(3p),  strcspn(3p),  strdup(3p),  strerror(3p),  strlen(3p),  strncat(3p),  strncmp(3p),  strncpy(3p),  strpbrk(3p),  strrchr(3p),  strsignal(3p),  strspn(3p),  strstr(3p),  strtok(3p),  strxfrm(3p)

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