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diff --git a/man/chmod.1 b/man/chmod.1 new file mode 100644 index 0000000..b6ed051 --- /dev/null +++ b/man/chmod.1 @@ -0,0 +1,174 @@ +.\" DO NOT MODIFY THIS FILE! It was generated by help2man 1.48.5. +.TH CHMOD "1" "August 2023" "GNU coreutils 9.4" "User Commands" +.SH NAME +chmod \- change file mode bits +.SH SYNOPSIS +.B chmod +[\fI\,OPTION\/\fR]... \fI\,MODE\/\fR[\fI\,,MODE\/\fR]... \fI\,FILE\/\fR... +.br +.B chmod +[\fI\,OPTION\/\fR]... \fI\,OCTAL-MODE FILE\/\fR... +.br +.B chmod +[\fI\,OPTION\/\fR]... \fI\,--reference=RFILE FILE\/\fR... +.SH DESCRIPTION +This manual page +documents the GNU version of +.BR chmod . +.B chmod +changes the file mode bits of each given file according to +.IR mode , +which can be either a symbolic representation of changes to make, or +an octal number representing the bit pattern for the new mode bits. +.PP +The format of a symbolic mode is [\c +\fBugoa\fP.\|.\|.][[\fB-+=\fP][\fIperms\fP.\|.\|.].\|.\|.], +where +.I "perms" +is either zero or more letters from the set +\fBrwxXst\fP, or a single letter from the set \fBugo\fP. +Multiple symbolic +modes can be given, separated by commas. +.PP +A combination of the letters \fBugoa\fP controls which users' access +to the file will be changed: the user who owns it (\fBu\fP), other +users in the file's group (\fBg\fP), other users not in the file's +group (\fBo\fP), or all users (\fBa\fP). If none of these are given, +the effect is as if (\fBa\fP) were +given, but bits that are set in the umask are not affected. +.PP +The operator \fB+\fP causes the selected file mode bits to be added to +the existing file mode bits of each file; \fB-\fP causes them to be +removed; and \fB=\fP causes them to be added and causes unmentioned +bits to be removed except that a directory's unmentioned set user and +group ID bits are not affected. +.PP +The letters \fBrwxXst\fP select file mode bits for the affected users: +read (\fBr\fP), write (\fBw\fP), execute (or search for directories) +(\fBx\fP), execute/search only if the file is a directory or already +has execute permission for some user (\fBX\fP), set user or group ID +on execution (\fBs\fP), restricted deletion flag or sticky bit +(\fBt\fP). Instead of one or more of these letters, you can specify +exactly one of the letters \fBugo\fP: the permissions granted to the +user who owns the file (\fBu\fP), the permissions granted to other +users who are members of the file's group (\fBg\fP), +and the permissions granted to users that are in neither of the two preceding +categories (\fBo\fP). +.PP +A numeric mode is from one to four octal digits (0\-7), derived by +adding up the bits with values 4, 2, and 1. Omitted digits are +assumed to be leading zeros. +The first digit selects the set user ID (4) and set group ID (2) and +restricted deletion or sticky (1) attributes. The second digit +selects permissions for the user who owns the file: read (4), write (2), +and execute (1); the third selects permissions for other users in the +file's group, with the same values; and the fourth for other users not +in the file's group, with the same values. +.PP +.B chmod +never changes the permissions of symbolic links; the +.B chmod +system call cannot change their permissions. This is not a problem +since the permissions of symbolic links are never used. +However, for each symbolic link listed on the command line, +.B chmod +changes the permissions of the pointed-to file. +In contrast, +.B chmod +ignores symbolic links encountered during recursive directory +traversals. +.SH "SETUID AND SETGID BITS" +.B chmod +clears the set-group-ID bit of a +regular file if the file's group ID does not match the user's +effective group ID or one of the user's supplementary group IDs, +unless the user has appropriate privileges. Additional restrictions +may cause the set-user-ID and set-group-ID bits of +.I MODE +or +.I RFILE +to be ignored. This behavior depends on the policy and +functionality of the underlying +.B chmod +system call. When in +doubt, check the underlying system behavior. +.PP +For directories +.B chmod +preserves set-user-ID and set-group-ID bits unless you +explicitly specify otherwise. You can set or clear the bits with +symbolic modes like +.B u+s +and +.BR g\-s . +To clear these bits for directories with a numeric mode requires +an additional leading zero like +.BR 00755 , +leading minus like +.BR \-6000 , +or leading equals like +.BR =755 . +.SH "RESTRICTED DELETION FLAG OR STICKY BIT" +The restricted deletion flag or sticky bit is a single bit, whose +interpretation depends on the file type. For directories, it prevents +unprivileged users from removing or renaming a file in the directory +unless they own the file or the directory; this is called the +.I "restricted deletion flag" +for the directory, and is commonly found on world-writable directories +like \fB/tmp\fP. For regular files on some older systems, the bit +saves the program's text image on the swap device so it will load more +quickly when run; this is called the +.IR "sticky bit" . +.SH OPTIONS +.PP +Change the mode of each FILE to MODE. +With \fB\-\-reference\fR, change the mode of each FILE to that of RFILE. +.TP +\fB\-c\fR, \fB\-\-changes\fR +like verbose but report only when a change is made +.TP +\fB\-f\fR, \fB\-\-silent\fR, \fB\-\-quiet\fR +suppress most error messages +.TP +\fB\-v\fR, \fB\-\-verbose\fR +output a diagnostic for every file processed +.TP +\fB\-\-no\-preserve\-root\fR +do not treat '/' specially (the default) +.TP +\fB\-\-preserve\-root\fR +fail to operate recursively on '/' +.TP +\fB\-\-reference\fR=\fI\,RFILE\/\fR +use RFILE's mode instead of specifying MODE values. +RFILE is always dereferenced if a symbolic link. +.TP +\fB\-R\fR, \fB\-\-recursive\fR +change files and directories recursively +.TP +\fB\-\-help\fR +display this help and exit +.TP +\fB\-\-version\fR +output version information and exit +.PP +Each MODE is of the form '[ugoa]*([\-+=]([rwxXst]*|[ugo]))+|[\-+=][0\-7]+'. +.SH AUTHOR +Written by David MacKenzie and Jim Meyering. +.SH "REPORTING BUGS" +GNU coreutils online help: <https://www.gnu.org/software/coreutils/> +.br +Report any translation bugs to <https://translationproject.org/team/> +.SH COPYRIGHT +Copyright \(co 2023 Free Software Foundation, Inc. +License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. +.br +This is free software: you are free to change and redistribute it. +There is NO WARRANTY, to the extent permitted by law. +.SH "SEE ALSO" +\fBchmod\fP(2) +.PP +.br +Full documentation <https://www.gnu.org/software/coreutils/chmod> +.br +or available locally via: info \(aq(coreutils) chmod invocation\(aq |