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diff --git a/man2/chmod.2 b/man2/chmod.2 deleted file mode 100644 index d7b9694..0000000 --- a/man2/chmod.2 +++ /dev/null @@ -1,347 +0,0 @@ -.\" Copyright (c) 1992 Drew Eckhardt (drew@cs.colorado.edu), March 28, 1992 -.\" and Copyright (C) 2006, 2014 Michael Kerrisk -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified by Michael Haardt <michael@moria.de> -.\" Modified 1993-07-21 by Rik Faith <faith@cs.unc.edu> -.\" Modified 1997-01-12 by Michael Haardt -.\" <michael@cantor.informatik.rwth-aachen.de>: NFS details -.\" Modified 2004-06-23 by Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.TH chmod 2 2023-10-31 "Linux man-pages 6.7" -.SH NAME -chmod, fchmod, fchmodat \- change permissions of a file -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <sys/stat.h> -.P -.BI "int chmod(const char *" pathname ", mode_t " mode ); -.BI "int fchmod(int " fd ", mode_t " mode ); -.P -.BR "#include <fcntl.h>" " /* Definition of AT_* constants */" -.B #include <sys/stat.h> -.P -.BI "int fchmodat(int " dirfd ", const char *" pathname ", mode_t " \ -mode ", int " flags ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.nf -.BR fchmod (): - Since glibc 2.24: - _POSIX_C_SOURCE >= 199309L -.\" || (_XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED) - glibc 2.19 to glibc 2.23 - _POSIX_C_SOURCE - glibc 2.16 to glibc 2.19: - _BSD_SOURCE || _POSIX_C_SOURCE - glibc 2.12 to glibc 2.16: - _BSD_SOURCE || _XOPEN_SOURCE >= 500 - || _POSIX_C_SOURCE >= 200809L - glibc 2.11 and earlier: - _BSD_SOURCE || _XOPEN_SOURCE >= 500 -.\" || (_XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED) -.fi -.P -.BR fchmodat (): -.nf - Since glibc 2.10: - _POSIX_C_SOURCE >= 200809L - Before glibc 2.10: - _ATFILE_SOURCE -.fi -.SH DESCRIPTION -The -.BR chmod () -and -.BR fchmod () -system calls change a file's mode bits. -(The file mode consists of the file permission bits plus the set-user-ID, -set-group-ID, and sticky bits.) -These system calls differ only in how the file is specified: -.IP \[bu] 3 -.BR chmod () -changes the mode of the file specified whose pathname is given in -.IR pathname , -which is dereferenced if it is a symbolic link. -.IP \[bu] -.BR fchmod () -changes the mode of the file referred to by the open file descriptor -.IR fd . -.P -The new file mode is specified in -.IR mode , -which is a bit mask created by ORing together zero or -more of the following: -.TP 18 -.BR S_ISUID " (04000)" -set-user-ID (set process effective user ID on -.BR execve (2)) -.TP -.BR S_ISGID " (02000)" -set-group-ID (set process effective group ID on -.BR execve (2); -mandatory locking, as described in -.BR fcntl (2); -take a new file's group from parent directory, as described in -.BR chown (2) -and -.BR mkdir (2)) -.TP -.BR S_ISVTX " (01000)" -sticky bit (restricted deletion flag, as described in -.BR unlink (2)) -.TP -.BR S_IRUSR " (00400)" -read by owner -.TP -.BR S_IWUSR " (00200)" -write by owner -.TP -.BR S_IXUSR " (00100)" -execute/search by owner ("search" applies for directories, -and means that entries within the directory can be accessed) -.TP -.BR S_IRGRP " (00040)" -read by group -.TP -.BR S_IWGRP " (00020)" -write by group -.TP -.BR S_IXGRP " (00010)" -execute/search by group -.TP -.BR S_IROTH " (00004)" -read by others -.TP -.BR S_IWOTH " (00002)" -write by others -.TP -.BR S_IXOTH " (00001)" -execute/search by others -.P -The effective UID of the calling process must match the owner of the file, -or the process must be privileged (Linux: it must have the -.B CAP_FOWNER -capability). -.P -If the calling process is not privileged (Linux: does not have the -.B CAP_FSETID -capability), and the group of the file does not match -the effective group ID of the process or one of its -supplementary group IDs, the -.B S_ISGID -bit will be turned off, -but this will not cause an error to be returned. -.P -As a security measure, depending on the filesystem, -the set-user-ID and set-group-ID execution bits -may be turned off if a file is written. -(On Linux, this occurs if the writing process does not have the -.B CAP_FSETID -capability.) -On some filesystems, only the superuser can set the sticky bit, -which may have a special meaning. -For the sticky bit, and for set-user-ID and set-group-ID bits on -directories, see -.BR inode (7). -.P -On NFS filesystems, restricting the permissions will immediately influence -already open files, because the access control is done on the server, but -open files are maintained by the client. -Widening the permissions may be -delayed for other clients if attribute caching is enabled on them. -.\" -.\" -.SS fchmodat() -The -.BR fchmodat () -system call operates in exactly the same way as -.BR chmod (), -except for the differences described here. -.P -If the pathname given in -.I pathname -is relative, then it is interpreted relative to the directory -referred to by the file descriptor -.I dirfd -(rather than relative to the current working directory of -the calling process, as is done by -.BR chmod () -for a relative pathname). -.P -If -.I pathname -is relative and -.I dirfd -is the special value -.BR AT_FDCWD , -then -.I pathname -is interpreted relative to the current working -directory of the calling process (like -.BR chmod ()). -.P -If -.I pathname -is absolute, then -.I dirfd -is ignored. -.P -.I flags -can either be 0, or include the following flag: -.TP -.B AT_SYMLINK_NOFOLLOW -If -.I pathname -is a symbolic link, do not dereference it: -instead operate on the link itself. -This flag is not currently implemented. -.P -See -.BR openat (2) -for an explanation of the need for -.BR fchmodat (). -.SH RETURN VALUE -On success, zero is returned. -On error, \-1 is returned, and -.I errno -is set to indicate the error. -.SH ERRORS -Depending on the filesystem, -errors other than those listed below can be returned. -.P -The more general errors for -.BR chmod () -are listed below: -.TP -.B EACCES -Search permission is denied on a component of the path prefix. -(See also -.BR path_resolution (7).) -.TP -.B EBADF -.RB ( fchmod ()) -The file descriptor -.I fd -is not valid. -.TP -.B EBADF -.RB ( fchmodat ()) -.I pathname -is relative but -.I dirfd -is neither -.B AT_FDCWD -nor a valid file descriptor. -.TP -.B EFAULT -.I pathname -points outside your accessible address space. -.TP -.B EINVAL -.RB ( fchmodat ()) -Invalid flag specified in -.IR flags . -.TP -.B EIO -An I/O error occurred. -.TP -.B ELOOP -Too many symbolic links were encountered in resolving -.IR pathname . -.TP -.B ENAMETOOLONG -.I pathname -is too long. -.TP -.B ENOENT -The file does not exist. -.TP -.B ENOMEM -Insufficient kernel memory was available. -.TP -.B ENOTDIR -A component of the path prefix is not a directory. -.TP -.B ENOTDIR -.RB ( fchmodat ()) -.I pathname -is relative and -.I dirfd -is a file descriptor referring to a file other than a directory. -.TP -.B ENOTSUP -.RB ( fchmodat ()) -.I flags -specified -.BR AT_SYMLINK_NOFOLLOW , -which is not supported. -.TP -.B EPERM -The effective UID does not match the owner of the file, -and the process is not privileged (Linux: it does not have the -.B CAP_FOWNER -capability). -.TP -.B EPERM -The file is marked immutable or append-only. -(See -.BR ioctl_iflags (2).) -.TP -.B EROFS -The named file resides on a read-only filesystem. -.SH VERSIONS -.SS C library/kernel differences -The GNU C library -.BR fchmodat () -wrapper function implements the POSIX-specified -interface described in this page. -This interface differs from the underlying Linux system call, which does -.I not -have a -.I flags -argument. -.SS glibc notes -On older kernels where -.BR fchmodat () -is unavailable, the glibc wrapper function falls back to the use of -.BR chmod (). -When -.I pathname -is a relative pathname, -glibc constructs a pathname based on the symbolic link in -.I /proc/self/fd -that corresponds to the -.I dirfd -argument. -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -.TP -.BR chmod () -.TQ -.BR fchmod () -4.4BSD, SVr4, POSIX.1-2001. -.TP -.BR fchmodat () -POSIX.1-2008. -Linux 2.6.16, -glibc 2.4. -.SH SEE ALSO -.BR chmod (1), -.BR chown (2), -.BR execve (2), -.BR open (2), -.BR stat (2), -.BR inode (7), -.BR path_resolution (7), -.BR symlink (7) |