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I have a batch script that starts a java server application inside of a screen. The command looks like this:

cd /dir/ && screen -A -m -d -S javascreen java -Xms640M -Xmx1024M -jar javaserverapp.jar nogui

After I run the batch script, it starts the server and puts it inside the correct screen. If I list my screens after, I see something like this:

user@gtwy /dir $ screen -list
There is a screen on:
        16180.javascreen       (Detached)
1 Socket in /var/run/screen/S-user.

However, I have a second batch script that sends automated commands to this server and runs on a different crontab interval. Because of the way the application works, I send commands to it like this (this command tells it to alert connected users "testing 123"):

screen -X exec .\!\! echo say testing 123

I've also tried:

screen -R -X exec .\!\! echo say testing 123
screen -S javascreen -X exec .\!\! echo say testing 123

Unfortunately, these commands DO NOT WORK. They don't even give me an error message, they just do nothing.

HOWEVER - If I manually attach to the screen first (with the below command) and then detach, now I can run any of the above commands flawlessly. I can demonstrate this with a video, if I wasn't clear enough here.

screen -r -d

Thanks in advance.

Update: here is the important parts of /etc/screenrc. It should be totally vanilla, I've never edited this file.

# ===============================================================
# No annoying audible bell, using "visual bell"
# vbell on                              # default: off
# vbell_msg "   -- Bell,Bell!! --   "   # default: "Wuff,Wuff!!"

# Automatically detach on hangup.
  autodetach on                         # default: on

# Don't display the copyright page
  startup_message off                   # default: on

# Uses nethack-style messages
# nethack on                            # default: off

# Affects the copying of text regions
  crlf off                              # default: off

# Enable/disable multiuser mode. Standard screen operation is singleuser.
# In multiuser mode the commands acladd, aclchg, aclgrp and acldel can be used
# to enable (and disable) other user accessing this screen session.
# Requires suid-root.
  multiuser off

# Change default scrollback value for new windows
  defscrollback 1000                    # default: 100

# Define the time that all windows monitored for silence should
# wait before displaying a message. Default 30 seconds.
  silencewait 15                        # default: 30

# bufferfile:   The file to use for commands
#               "readbuf" ('<') and  "writebuf" ('>'):
  bufferfile            $HOME/.screen_exchange
# hardcopydir:  The directory which contains all hardcopies.
# hardcopydir           ~/.hardcopy
# hardcopydir           ~/.screen
# shell:  Default process started in screen's windows.
# Makes it possible to use a different shell inside screen
# than is set as the default login shell.
# If begins with a '-' character, the shell will be started as a login shell.
# shell                 zsh
# shell                 bash
# shell                 ksh
  shell -$SHELL

# shellaka '> |tcsh'
# shelltitle '$ |bash'

# emulate .logout message
  pow_detach_msg "Screen session of \$LOGNAME \$:cr:\$:nl:ended."

# caption always " %w --- %c:%s"
# caption always "%3n %t%? @%u%?%? [%h]%?%=%c"

# advertise hardstatus support to $TERMCAP
# termcapinfo  * '' 'hs:ts=\E_:fs=\E\\:ds=\E_\E\\'

# set every new windows hardstatus line to somenthing descriptive
# defhstatus "screen: ^En (^Et)"

# don't kill window after the process died
# zombie "^["
share|improve this question
Have you got password protected session? – Ency Feb 13 '11 at 21:25
I don't believe so. I attempted to open ~/.screenrc to check this and found that I do not have a ~/.screenrc file. Is this a problem? Or is that normal? – James Watt Feb 13 '11 at 23:07
Instead of using screen to start a service, wouldn't it be easier to write a standard init script? – ℝaphink Feb 16 '11 at 7:45
up vote 2 down vote accepted

Sadrul on #screen (Freenode) gave this answer, and it worked:

with the -X commands, try specifying the window number as well (e.g. screen -p0 -X ...)

share|improve this answer
Excellent! Wasted almost two days before I've finally found this... – vines Dec 11 '11 at 19:35
Glad it helped someone else! – James Watt Jan 12 '12 at 15:14

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