| .\" Copyright 2013 Michael Kerrisk <mtk.manpages@gmail.com> |
| .\" (Replaces an earlier page by Walter Harms and Michael Kerrisk) |
| .\" |
| .\" %%%LICENSE_START(VERBATIM) |
| .\" Permission is granted to make and distribute verbatim copies of this |
| .\" manual provided the copyright notice and this permission notice are |
| .\" preserved on all copies. |
| .\" |
| .\" Permission is granted to copy and distribute modified versions of this |
| .\" manual under the conditions for verbatim copying, provided that the |
| .\" entire resulting derived work is distributed under the terms of a |
| .\" permission notice identical to this one. |
| .\" |
| .\" Since the Linux kernel and libraries are constantly changing, this |
| .\" manual page may be incorrect or out-of-date. The author(s) assume no |
| .\" responsibility for errors or omissions, or for damages resulting from |
| .\" the use of the information contained herein. The author(s) may not |
| .\" have taken the same level of care in the production of this manual, |
| .\" which is licensed free of charge, as they might when working |
| .\" professionally. |
| .\" |
| .\" Formatted or processed versions of this manual, if unaccompanied by |
| .\" the source, must acknowledge the copyright and authors of this work. |
| .\" %%%LICENSE_END |
| .\" |
| .TH CANONICALIZE_FILE_NAME 3 2021-03-22 "GNU" "Linux Programmer's Manual" |
| .SH NAME |
| canonicalize_file_name \- return the canonicalized absolute pathname |
| .SH SYNOPSIS |
| .nf |
| .BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */" |
| .B #include <stdlib.h> |
| .PP |
| .BI "char *canonicalize_file_name(const char *" path ");" |
| .fi |
| .SH DESCRIPTION |
| The |
| .BR canonicalize_file_name () |
| function returns a null-terminated string containing |
| the canonicalized absolute pathname corresponding to |
| .IR path . |
| In the returned string, symbolic links are resolved, as are |
| .I . |
| and |
| .I .. |
| pathname components. |
| Consecutive slash |
| .RI ( / ) |
| characters are replaced by a single slash. |
| .PP |
| The returned string is dynamically allocated by |
| .BR canonicalize_file_name () |
| and the caller should deallocate it with |
| .BR free (3) |
| when it is no longer required. |
| .PP |
| The call |
| .I canonicalize_file_name(path) |
| is equivalent to the call: |
| .PP |
| realpath(path, NULL); |
| .SH RETURN VALUE |
| On success, |
| .BR canonicalize_file_name () |
| returns a null-terminated string. |
| On error (e.g., a pathname component is unreadable or does not exist), |
| .BR canonicalize_file_name () |
| returns NULL and sets |
| .I errno |
| to indicate the error. |
| .SH ERRORS |
| See |
| .BR realpath (3). |
| .SH ATTRIBUTES |
| For an explanation of the terms used in this section, see |
| .BR attributes (7). |
| .ad l |
| .nh |
| .TS |
| allbox; |
| lbx lb lb |
| l l l. |
| Interface Attribute Value |
| T{ |
| .BR canonicalize_file_name () |
| T} Thread safety MT-Safe |
| .TE |
| .hy |
| .ad |
| .sp 1 |
| .SH CONFORMING TO |
| This function is a GNU extension. |
| .SH SEE ALSO |
| .BR readlink (2), |
| .BR realpath (3) |