Commands tagged PROMPT_COMMAND (4)

  • Change Title of Terminal Window to Verbose Info useful at Login

    I usually have 5 or more ssh connections to various servers, and putting this command in my .bash_profile file makes my putty window or x terminal window title change to this easily recognizable and descriptive text. Includes the username, group, server hostname, where I am connecting from (for SSH tunneling), which device pts, current server load, and how many processes are running. You can also use this for your PROMPT_COMMAND variable, which updates the window title to the current values each time you exec a command. I prefix running this in my .bash_profile with [[ ! -z "$SSH_TTY" ]] && which makes sure it only does this when connecting via SSH with a TTY. Here's some rougher examples from http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html # If set, the value is executed as a command prior to issuing each primary prompt. #H=$((hostname || uname -n) 2>/dev/null | sed 1q);W=$(whoami) #export PROMPT_COMMAND='echo -ne "\033]0;${W}@${H}:${PWD/#$HOME/~} ${SSH_TTY/\/dev\//} [`uptime|sed -e "s/.*: \([^,]*\).*/\1/" -e "s/ //g"`]\007"' #PROMPT_COMMAND='echo -ne "\033]0;`id -un`:`id -gn`@`hostname||uname -n 2>/dev/null|sed 1q` `command who -m|sed -e "s%^.* \(pts/[0-9]*\).*(\(.*\))%[\1] (\2)%g"` [`uptime|sed -e "s/.*: \([^,]*\).*/\1/" -e "s/ //g"` / `command ps aux|wc -l`]\007"' #[[ -z "$SSH_TTY" ]] || export PROMPT_COMMAND #[[ -z "$SSH_TTY" ]] && [[ -f /dev/stdout ]] && SSH_TTY=/dev/stdout And here's a simple function example for setting the title: function set_window_title(){ echo -e "\033]0; ${1:-$USER@$HOST - $SHLVL} \007"; } Show Sample Output


    4
    echo -ne "\033]0;`id -un`:`id -gn`@`hostname||uname -n|sed 1q` `who -m|sed -e "s%^.* \(pts/[0-9]*\).*(\(.*\))%[\1] (\2)%g"` [`uptime|sed -e "s/.*: \([^,]*\).*/\1/" -e "s/ //g"` / `ps aux|wc -l`]\007"
    AskApache · 2009-09-19 06:57:53 5
  • Colour part of your prompt red to indicate an error

    If the return code from the last command was greater than zero, colour part of your prompt red. The commands give a prompt like this: [user current_directory]$ After an error, the "[user" part is automatically coloured red. Tested using bash on xterm and terminal. Place in your .bashrc or .bash_profile.


    3
    export PROMPT_COMMAND='if (($? > 0)); then echo -ne "\033[1;31m"; fi'; export PS1='[\[\]\u\[\033[0m\] \[\033[1;34m\]\w\[\033[0m\]]\$ '
    quintic · 2010-08-25 21:19:30 4
  • Annoying PROMPT_COMMAND animation

    unset PROMPT_COMMAND to disable. Show Sample Output


    2
    PROMPT_COMMAND='seq $COLUMNS | xargs -IX printf "%Xs\r" @'
    unefunge · 2010-11-24 14:34:21 41
  • Colour part of your prompt red to indicate an error


    -2
    export PS1='[\[\e[36;1m\]\u@\[\e[32;1m\]\h \[\e[31;1m\]\w]# \[\e[0m\]'
    bakhru · 2011-04-16 00:58:51 6

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

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