how to run multiple bash scripts in 1 bash command ?
i use command
bash script1.sh
how to make it run multiple commands in 1 command ?
for example
bash script1.sh bash script2.sh bash script3.sh bash script4.sh
Please help
If you want to run all bash script in //:
for i in {1..4}; do bash "script${i}.sh" & done
If you put the control operator & at the end of a command, e.g. command &, the shell executes the command in the background in a subshell. The shell does not wait for the command to finish, and the return status is 0. Pid of the last backgrounded command is available via the special variable $!
If instead you want to run sequentially, use
printf '%s\n' script{1..4}.sh | xargs -n1 bash
or
for i in {1..4}; do bash "script${i}.sh"; done
Related
I have a bash script that opens up a shell called salome shell and it should execute a command called as_run in that shell. The thing is that after entering the salome shell it doesn't execute the command until I exit the salome shell. This is the code that i got:
#!/bin/bash
cd /opt/salome/appli_V2018.0.1_public
./salome shell
eval "as_run /home/students/gbroilo/Desktop/Script/Template_1_2/exportSalome"
What should I do in order to execute the command in the salome shell?
Might be this is what you want:
# call salome shell with commands in a specified script file
cd /opt/salome/appli_V2018.0.1_public
./salome shell <"/home/students/gbroilo/Desktop/Script/Template_1_2/exportSalome"
Or might be this is what you want:
# pipe a command as_run... to salome shell
cd /opt/salome/appli_V2018.0.1_public
echo "as_run /home/students/gbroilo/Desktop/Script/Template_1_2/exportSalome" | ./salome shell
Anyway, you have to read the salome guide about how salome shell call it's script.
Most shells implement a way to pass the commands as parameters, e.g.
dash -c 'x=1 ; echo $x'
You'll need to consult your shell's manual to see if it's possible.
You can also try sending the commands to the standard input of the shell:
echo 'set x = 1 ; echo $x' | tcsh
Using a HERE doc might be a bit more readable in case of complex commands:
tcsh << 'TCSH'
set x = 1
echo $x
TCSH
I am using CentOS 7.6 and bash shell inside VirtualBox .
I came across a script named MotherScript in my site having this statement :
nohup ksh MyScript &
Both MotherScript and MyScript have a shebang line
#!/bin/ksh
After login, I just fire the MotherScript.
In my previous companies, usually, I used this statement :
nohup MyScript &
Is there any functional/strange/usage difference between these 2 statements ?
Inside MyScript, there is a sleep command to sleep 1 hour repeatedly in a while loop for 7 days.
However, very strange, I cannot see this sleep process using :
ps -ef | grep sleep
Therefore, I cannot kill the sleep process.
Does this nohup ksh play the trick ?
Anyone know the reason behind ?
Thanks.
Alvin
nohup ksh MyScript &
This will run the script using ksh(korn) shell.
nohup MyScript &
This will pick your default shell which you can check using below command
echo $SHELL
you can also change default shell using chsh Utility
I have a bash script and need to run some commands in cshell inside it.
#!/bin/bash
echo entering_to_cshell
csh
echo in_cshell
exit
echo exited_from_cshell
Why doesn't this script run as expected? It only prints entering_to_cshell and it doesn't exit from cshell.
By using
csh
you start a new subshell where your script isn't executed. That's why none of your following commands are executed. Your script waits for this subshell to end which, as you noted, never happens.
Try
csh -c "echo in_cshell"
This way you don't create a new subshell which isn't impacted by your script.
By simply calling csh in your script, you're starting an interactive csh subshell. You'll notice that once you quit from the csh session, your script will then continue to with the subsequent echo and quiting on exit.
To pass a series of commands to csh from you bash script, one approach would be to use the Here Document syntax to redirect commands to csh.
#!/bin/bash
echo entering_to_cshell
csh <<EOF
echo in_cshell
exit
EOF
echo exited_from_cshell
The lines between the EOF entries will be treated as a script that is interpreted by csh.
I have a shell script which will print another shell script to stdout. I need to execute both the scripts (initial script and output script) with a single line bash command. Is it possible?
Maybe something like that:
sh ./test.sh | sh
Try doing this :
bash test.bash | bash -s
Are there actions in Bash other than pipes and command substitution that start a new subshell?
Putting a command chain in parens (( ... )) also starts a new subshell.
( cd /tmp ; pwd ) ; pwd
Each shell script running is, in effect, a subprocess (child process) of the parent shell.
A shell script can itself launch subprocesses. These subshells let the script do parallel processing, in effect executing multiple subtasks simultaneously.
say you have script test.sh. After you run it if you run the command
ps -ef|grep -i test.sh
you will see the it runs with different PID
In general, an external command in a script forks off a subprocess/subshell