Showing GNU screen session name and window title in shell prompt

Question

Is there a way to present the GNU Screen session name and window title in the prompt of the shell (let us say, the Bash prompt defined by PS1)?

Answer 1

Screen supplies some environment variables (from screen(1) manpage):

STY              Alternate socket name.
WINDOW           Window number of a window (at creation time).

The "at creation time" means that if you renumber a window (using screen's number command), the shell will not be told about the change and $WINDOW will still be the same as the first window number.

You could use something like:

PS1='\u@\h(${STY}:${WINDOW}):\w$ '

Answer 2

I always use precise screen session names. Then I can add screen's STY env var, with the numeric id stripped out (thanks dimo414), to PS1. I don't decorate it with curly braces or anything because I'm not always in a session. Simple example:

PS1='\u@\h ${STY#[0-9]*.} \w$ '

Answer 3

I use this:

(`echo ${STY} | sed -e 's/[0-9]*\.//g'`:${WINDOW}:`screen -Q title`)

removes the process number from ${STY}
includes the window number (as mentioned "at creation time")
includes the window title (as returned from screen -Q title)

notes:

• first time it runs, screen -Q waits for a return keystroke
• i set the window title with C-a C-A and then source my .profile to update the prompt

Answer 4

I generally use named screens, e.g.: screen -S vim ## see: screen -h

To get a PS1 prompt in the screen that shows the name of the screen session (to differentiate screen sessions for the normal terminal sessions) I needed a two-part approach.

1. Set the prompt in a ~/.screenrc file.
2. Source that file (within the screen session) via a normal BASH ~/.bashrc alias.

# -----------------------------------------------------------------------------
# ~/.screenrc    ## or whatever you want to name it

PS1='[\u@\h (screen: ${STY#[0-9]*.}) \w]$ '
# -----------------------------------------------------------------------------

# -----------------------------------------------------------------------------
# ~/.bashrc

alias ssrc='source ~/.screenrc'    ## or whatever you named it (comment above)
# -----------------------------------------------------------------------------

Usage:

[me@vps1360 ~]$ screen -S test

  # -----------------------------------------------------------------------------
  # Named screen session:

  [me@vps1360 ~]$ ssrc
  [me@vps1360 (screen: test) ~]$    ## PS1 prompt with screen session name
  # Ctrl-a d
  [detached from 9278.test]
  # -----------------------------------------------------------------------------

[me@vps1360 ~]$