projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 3f162d28 C |
1 | .TH CHMOD 1 "18 January 1983" |
| 2 | .SH NAME | |
| 3 | chmod \- change mode | |
| 4 | .SH SYNOPSIS | |
| 5 | \fBchmod\fP mode file ... | |
| 6 | .SH DESCRIPTION | |
| 7 | The mode of each named file is changed according to \fImode\fP, | |
| 8 | which may be absolute or symbolic. An absolute \fImode\fP | |
| 9 | is an octal number constructed from the OR of the following modes: | |
| 10 | .TP 10 | |
| 11 | 4000 | |
| 12 | set user ID on execution | |
| 13 | .br | |
| 14 | .ns | |
| 15 | .TP 10 | |
| 16 | 2000 | |
| 17 | set group ID on execution | |
| 18 | .br | |
| 19 | .ns | |
| 20 | .TP 10 | |
| 21 | 1000 | |
| 22 | sticky bit, see | |
| 23 | .IR chmod (2) | |
| 24 | .br | |
| 25 | .ns | |
| 26 | .TP 10 | |
| 27 | 0400 | |
| 28 | read by owner | |
| 29 | .br | |
| 30 | .ns | |
| 31 | .TP 10 | |
| 32 | 0200 | |
| 33 | write by owner | |
| 34 | .br | |
| 35 | .ns | |
| 36 | .TP 10 | |
| 37 | 0100 | |
| 38 | execute (search in directory) by owner | |
| 39 | .br | |
| 40 | .ns | |
| 41 | .TP 10 | |
| 42 | 0070 | |
| 43 | read, write, execute (search) by group | |
| 44 | .br | |
| 45 | .ns | |
| 46 | .TP 10 | |
| 47 | 0007 | |
| 48 | read, write, execute (search) by others | |
| 49 | .LP | |
| 50 | A symbolic \fImode\fP has the form: | |
| 51 | .IP | |
| 52 | .RI [ who ] | |
| 53 | \fIop permission\fP | |
| 54 | .RI [ "op permission" "] ..." | |
| 55 | .LP | |
| 56 | The \fIwho\fP part is a combination of the letters \fBu\fP | |
| 57 | (for user's permissions), \fBg\fP (group) and \fBo\fP (other). | |
| 58 | The letter \fBa\fP stands for all, or \fBugo.\fP | |
| 59 | If \fIwho\fP is omitted, the default is \fIa\fP | |
| 60 | but the setting of the file creation mask (see umask(2)) is taken into account. | |
| 61 | .LP | |
| 62 | \fIOp\fP can be \fB+\fP to add \fIpermission\fP to the file's mode, | |
| 63 | \fB\-\fP to take away \fIpermission\fP and \fB=\fP to assign | |
| 64 | \fIpermission\fP absolutely (all other bits will be reset). | |
| 65 | .LP | |
| 66 | \fIPermission\fP is any combination of the letters \fBr\fP (read), | |
| 67 | \fBw\fP (write), \fBx\fP (execute), \fBs\fP (set owner or group id) | |
| 68 | and \fBt\fP (save text \- sticky). Letters | |
| 69 | .BR u, | |
| 70 | \fBg\fP or \fBo\fP indicate that \fIpermission\fP | |
| 71 | is to be taken from the current mode. Omitting \fIpermission\fP | |
| 72 | is only useful with \fB=\fP to take away all permissions. | |
| 73 | .SH EXAMPLES | |
| 74 | .LP | |
| 75 | The first example denies write permission to others, | |
| 76 | the second makes a file executable: | |
| 77 | .IP | |
| 78 | chmod o\-w file | |
| 79 | .br | |
| 80 | chmod +x file | |
| 81 | .LP | |
| 82 | Multiple symbolic modes separated by commas may be given. | |
| 83 | Operations are performed in the order specified. The letter | |
| 84 | \fBs\fP is only useful with \fBu\fP or \fBg.\fP | |
| 85 | .LP | |
| 86 | Only the owner of a file (or the super-user) may change its mode. | |
| 87 | .SH "SEE ALSO" | |
| 88 | ls(1), chmod(2), stat(2), umask(2), chown(8) | |
| 89 | .SH MESSAGES | |
| 90 | .LP | |
| 91 | .IP "Usage: chmod [ugoa][+-=][rwxstugo] file ..." 10 | |
| 92 | .br | |
| 93 | Standard memory jogger message indicating how to use the \fIchmod\fP command. | |
| 94 | .IP "chmod: can't access \fIfilename\fP" 10 | |
| 95 | .br | |
| 96 | The file or directory specified by \fIfilename\fP does not exist. | |
| 97 | .IP "chmod: can't change \fIfilename\fP" 10 | |
| 98 | .br | |
| 99 | You are trying to change permissions on a file or directory which you don't own. | |
| 100 | .IP "chmod: invalid mode" 10 | |
| 101 | .br | |
| 102 | The file mode specified on the command line is incorrect. This often | |
| 103 | happens when you type the filename first and the mode second. |