Script command losing alias from shell - linux

When I run the script command it loses all the aliases from the existing shell which is not desired for people using lots of aliases. So, I am trying to see if I can automatically source the .profile again to see if it works without the user have to do it.
Here below is the code:
#!/bin/bash -l
rm aliaspipe
mkfifo aliaspipe
bash -c "sleep 1;echo 'source ~/.bash_profile' > aliaspipe ;echo 'alias' > aliaspipe ;echo 'exec 0<&-' > aliaspipe"&
echo "starting script for recording"
script < aliaspipe
Basically I am creating a named pipe and the making the pipe as stdin to the script program, trying to run the source command and then close the stdin from pipe to the terminal stdin so that I can continue with the script.
But when I execute, the script is exiting after I execute "exec 0<&-",
bash-3.2$ exec 0<&-
bash-3.2$ exit
Script done, output file is typescript
Not sure why the exit is called and script is terminated. If I can make the script move the stdin from pipe to terminal then it should be fine.

You can get script to execute a bash login shell by telling it to do so explicitly.
# Gnu script (most Linux distros)
script -c "bash -l"
# BSD script (also Mac OS X)
script typescript bash -l
That will cause your .bash_profile to be sourced.
By the way, redirections are not stacks. When you write exec 0<&-, you're closing standard input, and when bash's standard input is closed, it exits.

Related

How can I automatically record the terminal session every time a new terminal window is opened?

I have a script I would like to run when a terminal is opened. This will use the script command to record the terminal session, to aid in troubleshooting the system after some software work is done. When I placed the script in .bash.d, and opened a terminal, it gets stuck in a loop repeatedly starting the script.
script -a -f ~/user_data/error_logs/terminal_output/typescript.$(hostname).$(date -I).txt
I was able to fix it by placing the following in the .bashrc
test "$(ps -ocommand= -p $PPID | awk '{print $1}')" == 'script' || (/data/file_upload/term_log.sh)
The contents of term_log.sh are:
script -a -f -q ~/user_data/error_logs/terminal_output/typescript.txt
kill -9 $PPID
I added the kill -9 $PPID so that when a user typed exit it would close the terminal and not just quit the script.
I have never used bash.d. But I put commands I would like to run at the start of terminal or more specifically bash in ~/.bash_profile and it works like charm.
You will have to close the bash session and start a fresh session for the command you put in ~/.bash_profile to take effect, as commands in ~/.bash_profile are executed only when the bash session starts. Alternatively, after you have put the command in ~/.bash_profile, you can run source ~/.bash_profile for the command to take effect.

ssh does not return even after execution

The following ssh command does not return to terminal. It hangs though the execution is completed. The execution hangs after echo hi command.
ssh user#testserver "echo hello;source .profile;source .bash_profile;/apps/myapp/deploytools/ciInstallAndRun.sh; echo hi"
Output
hello
<outoutfrom remote script"
hi
ciInstallAndRun.sh
echo 'starting'
cd /apps/myapp/current
./tctl kill
cd /apps/myapp
mv myapp_v1.0 "myapp_v1.0_`date '+%Y%m%d%H%M'`"
unzip -o /apps/myapp/myappdist-bin.zip
java -classpath .:/apps/myapp/deploytools/cleanup.jar se.telenor.project.cleanup.Cleanup /apps/myapp myapp_v1.0_ 3
cd /apps/myapp/myapp_v1.0
echo 'Done with deploy'
chmod -R 775 *
echo 'Done'
./tctl start test
Source OS: Redhat
Dest Os: Solaris 10 8/07
Any idea to fix this.
Any idea to fix this.
Your installation script has spawned a child process.
Add a ps -f or ptree $$ command before echo hi. You'll see a child process or multiple child processes spawned by your install script.
To stop the SSH command from hanging, you need to detach such child process(es) from your terminal's input/output. You can sedirect your script's output to a file - both stdout and stderr with > /some/output/file 2>&1, and also redirect its input with < /dev/null.
Or you can use the nohup command.
You haven't provided an MCVE, as others have noted, but this is likely the problem command in you install script, since your question implies that you see the expected output from your install script:
./tctl start test
You probably would do better to replace it with something like:
./tctl start test </dev/null >/some/log/file/path.log 2>&1

Launching a bash shell from a sudo-ed environment

Apologies for the confusing Question title. I am trying to launch an interactive bash shell from a shell script ( say shel2.sh) which has been launched by a parent script (shel1.sh) in a sudo-ed environment. ( I am creating a guided deployment
script for my software which needs to be installed as super-user , hence the sudo, but may need the user to access the shell. )
Here's shel1.sh
#!/bin/bash
set -x
sudo bash << EOF
echo $?
./shel2.sh
EOF
echo shel1 done
And here's shel2.sh
#!/bin/bash
set -x
bash --norc --verbose --noprofile -i
echo $?
echo done
I expected this to launch an interactive bash shell which waits for my input before returning to shel1.sh. This is what I see:
+ ./shel1.sh
+ sudo bash
0
+ bash --norc --verbose --noprofile -i
bash-4.3# exit
+ echo 0
0
+ echo done
done
+ echo shel1 done
shel1 done
The bash-4.3# calls an exit automatically and quits. Interestingly if I invoke the bash shell with -l (or --login) the automatic entry is logout !
Can someone explain what is happening here ?
When you use a here document, you are tying up the shell's -- and its spawned child processes' -- standard input to the here document input.
You can avoid using a here document in many situations. For example, replace the here document with a single-quoted string.
#!/bin/bash
set -x
sudo bash -c '
# Aside: How is this actually useful?
echo $?
# Spawned script inherits the stdin of "sudo bash"
./shel2.sh'
echo shel1 done
Without more details, it's hard to see where exactly you want to go with this, but most modern Linux platforms have package managers which allow all kinds of hooks for installation, so that you would typically not need to do this sort of thing. Have you looked into that?

Read command in bash script not waiting for user input when piped to bash?

Here is what I'm entering in Terminal:
curl --silent https://raw.githubusercontent.com/githubUser/repoName/master/installer.sh | bash
The WordPress installing bash script contains a "read password" command that is supposed to wait for users to input their MySQL password. But, for some reason, that doesn't happen when I run it with the "curl githubURL | bash" command. When I download the script via wget and run it via "sh installer.sh", it works fine.
What could be the cause of this? Any help is appreciated!
If you want to run a script on a remote server without saving it locally, you can try this.
#!/bin/bash
RunThis=$(lynx -dump http://127.0.0.1/example.sh)
if [ $? = 0 ] ; then
bash -c "$RunThis"
else
echo "There was a problem downloading the script"
exit 1
fi
In order to test it, I wrote an example.sh:
#!/bin/bash
# File /var/www/example.sh
echo "Example read:"
read line
echo "You typed: $line"
When I run Script.sh, the output looks like this.
$ ./Script.sh
Example read:
Hello World!
You typed: Hello World!
Unless you absolutely trust the remote scripts, I would avoid doing this without examining it before executing.
It wouldn't stop for read:
As when you are piping in a way you are forking a child which has been given input from parent shell.
You cannot give the values back to parent(modify parent's env) from child.
and through out this process you are always in parent process.

Run a shell script in new terminal from current terminal

How do you run a shell script in a new terminal in Linux from a terminal like "start test.bat" in Windows, also it should be working in the console mode.
Here's a simple example to get you started:
To write a shell script, do this on your command prompt:
echo -e '#!/bin/sh\n echo "hello world"' > abc.sh
This writes:
#!/bin/sh
echo "hello world"
To a file called abc.sh
Next, you want to set it to executable by:
chmod +x abc.sh
Now, you can run it by:
./abc.sh
And you should see:
hello world
On your terminal.
To run it in a new terminal, you can do:
gnome-terminal -x ./abc.sh
or, if it's xterm:
xterm -e ./abc.sh
Here's a list of different terminal emulators.
Alternatively, you just run it in your current terminal, but background it instead by:
./abc.sh &
I came here wanting to figure out how to make a script spawn a terminal and run it self in it, so for those who want to do that I figured out this solution:
if [ ! -t 0 ]; then # script is executed outside the terminal?
# execute the script inside a terminal window with same arguments
x-terminal-emulator -e "$0" "$#"
# and abort running the rest of it
exit 0
fi
For gnome try this.
Replace ls with the command you want to run
gnome-terminal -x sh -c "ls|less"
I hope this is what you want
As of January 2020, the -e and -x option in gnome-terminal still run properly but throw out the following warnings:
For -e:
# Option “-e” is deprecated and might be removed in a later version
of gnome-terminal.
# Use “-- ” to terminate the options and put the command line to
execute after it.
For -x:
# Option “-x” is deprecated and might be removed in a later version
of gnome-terminal.
# Use “-- ” to terminate the options and put the command line to
execute after it.
Based on that information above, I confirmed that you can run the following two commands without receiving any warning messages:
gnome-terminal -- /bin/sh -c '<your command>'
gnome-terminal -- ./<your script>.sh
I hope this helps anyone else presently having this issue :)

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