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| .\" @(#)wall.1 6.5 (Berkeley) 4/23/91 |
| .\" |
| .TH WALL "1" "August 2013" "util-linux" "User Commands" |
| .SH NAME |
| wall \- write a message to all users |
| .SH SYNOPSIS |
| .B wall |
| .RB [ \-n ] |
| .RB [ \-t |
| .IR timeout ] |
| .RB [ \-g |
| .IR group ] |
| .RI [ message " | " file ] |
| .SH DESCRIPTION |
| .B wall |
| displays a |
| .IR message , |
| or the contents of a |
| .IR file , |
| or otherwise its standard input, on the terminals of all currently logged |
| in users. The command will wrap lines that are longer than 79 characters. |
| Short lines are whitespace padded to have 79 characters. The command will |
| always put a carriage return and new line at the end of each line. |
| .PP |
| Only the superuser can write on the terminals of users who have chosen to |
| deny messages or are using a program which automatically denies messages. |
| .PP |
| Reading from a |
| .I file |
| is refused when the invoker is not superuser and the program is |
| set-user-ID or set-group-ID. |
| .SH OPTIONS |
| .TP |
| .BR \-n , " \-\-nobanner" |
| Suppress the banner. |
| .TP |
| .BR \-t , " \-\-timeout " \fItimeout\fR |
| Abandon the write attempt to the terminals after \fItimeout\fR seconds. |
| This \fItimeout\fR must be a positive integer. The default value |
| is 300 seconds, which is a legacy from the time when people ran terminals over |
| modem lines. |
| .TP |
| .BR \-g , " \-\-group " \fIgroup\fR |
| Limit printing message to members of group defined as a |
| .I group |
| argument. The argument can be group name or GID. |
| .TP |
| .BR \-V , " \-\-version" |
| Display version information and exit. |
| .TP |
| .BR \-h , " \-\-help" |
| Display help text and exit. |
| .SH NOTES |
| Some sessions, such as wdm, that have in the beginning of |
| .BR utmp (5) |
| ut_type data a ':' character will not get the message from |
| .BR wall . |
| This is done to avoid write errors. |
| .SH SEE ALSO |
| .BR mesg (1), |
| .BR talk (1), |
| .BR write (1), |
| .BR shutdown (8) |
| .SH HISTORY |
| A |
| .B wall |
| command appeared in Version 7 AT&T UNIX. |
| .SH AVAILABILITY |
| The wall command is part of the util-linux package and is available from |
| .UR https://\:www.kernel.org\:/pub\:/linux\:/utils\:/util-linux/ |
| Linux Kernel Archive |
| .UE . |