canonicalize_file_name(3) Library Functions Manual canonicalize_file_name(3)
NAME
canonicalize_file_name - return the canonicalized absolute pathname
LIBRARY
Standard C library (libc, -lc)
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 canonical-
ize_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),
canonicalize_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 attrib-
utes(7).
┌───────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├───────────────────────────────────────────┼───────────────┼─────────┤
│ canonicalize_file_name() │ Thread safety │ MT-Safe │
└───────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
GNU.
SEE ALSO
readlink(2), realpath(3)
Linux man-pages 6.7 2023-10-31 canonicalize_file_name(3)
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