CANONICALIZE_FILE_NAME(3)                                               Linux Programmer's Manual                                              CANONICALIZE_FILE_NAME(3)

NAME
       canonicalize_file_name - return the canonicalized absolute pathname

SYNOPSIS
       #define _GNU_SOURCE         /* See feature_test_macros(7) */
       #include <stdlib.h>

       char *canonicalize_file_name(const char *path);

DESCRIPTION
       The  canonicalize_file_name()  function  returns  a null-terminated string containing the canonicalized absolute pathname corresponding to path.  In the returned
       string, symbolic links are resolved, as are .  and ..  pathname components.  Consecutive slash (/) characters are replaced by a single slash.

       The returned string is dynamically allocated by canonicalize_file_name() and the caller should deallocate it with free(3) when it is no longer required.

       The call canonicalize_file_name(path) is equivalent to the call:

           realpath(path, NULL);

RETURN VALUE
       On success, canonicalize_file_name() returns a null-terminated string.  On error (e.g., a pathname  component  is  unreadable  or  does  not  exist),  canonical‐
       ize_file_name() returns NULL and sets errno to indicate the error.

ERRORS
       See realpath(3).

ATTRIBUTES
       For an explanation of the terms used in this section, see attributes(7).

       ┌──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │Interface                                                                                                                             │ Attribute     │ Value   │
       ├──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │canonicalize_file_name()                                                                                                              │ Thread safety │ MT-Safe │
       └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO
       This function is a GNU extension.

SEE ALSO
       readlink(2), realpath(3)

GNU                                                                            2021-03-22                                                      CANONICALIZE_FILE_NAME(3)