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canonicalize_file_name(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | STANDARDS | SEE ALSO | COLOPHON 

canonical...file_name(3) Library Functions Manualcanonical...file_name(3)

NAME         top

       canonicalize_file_name - return the canonicalized absolute
       pathname

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

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

       char *canonicalize_file_name(const char *path);

DESCRIPTION         top

       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         top

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

ERRORS         top

       See realpath(3).

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
       โ”‚ Interface                            โ”‚ Attribute     โ”‚ Value   โ”‚
       โ”œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ค
       โ”‚ canonicalize_file_name()             โ”‚ Thread safety โ”‚ MT-Safe โ”‚
       โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜

STANDARDS         top

       GNU.

SEE ALSO         top

       readlink(2), realpath(3)

COLOPHON         top

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Linux man-pages 6.18            2026-02-08       canonical...file_name(3)

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