This is a sample of a problem I'm having - trying to declare an array in Upstart. I can run the declare line on the bash prompt but when done via an upstart script - it fails silently.
description "bla"
author "yea"
start on runlevel [2345]
script
echo "yo" >> /var/log/arr.log 2>&1
declare -a MYARR=("1,2" "3,4")
echo "stuff"
end script
I'm doing this on ubuntu 14.04
Thanks!
Script code will be executed using /bin/sh. Arrays won't work in pure bourne shell.
Take a look at How to use array in sh shell.
Related
I just started to learn shells scripting.
Trying to run script in cron, without success. In telnet when i run "sh.script.sh" output is as expected. What I miss?
script.sh is in /usr/bin folder.
#!/bin/sh
var1 = $(opkg update)
echo ${var1}
try simply this:
#!/usr/bin/env bash
var1=$(opkg update)
echo $var1
I used to work with UNIX a couple years ago, and I am just starting to get back into it again. I was wondering if anyone could help me with a question.
For example, if I am in bash, I say chsh --shell /bin/tcsh after this I am prompted to enter my password. If I try to say echo $SHELL it will not tell me I have changed shells. It still tells me I am in bash, not C shell. So I have to exit and restart. Once I log back it, then it tells I am in C shell.
Is there a more effective method to change shells? One that does not require me having to log in and out?
Thank you in advance.
chsh(1): change your login shell
Once you change your shell with chsh, it should automatically login to that shell every time you open a terminal.
If you want to use a different shell temporary, just run that shell directly: "tcsh", "zsh", etc..
If you want to use a particular shell for a script use shebang "#!".
Example -- The following on the first line of a shell script will ensure the script is run with sh (and you can do this for any shell available on your system):
#!/bin/sh
Always check your current shell by using :
echo $0
That way you will get the exact process ( your current shell ) you are running. If you print $SHELL it will return to you the default shell that will be open when you login to the server which unless that's what you need its not reliable.
ubuntu$ echo $SHELL
/bin/bash
ubuntu$ echo $0
-bash
ubuntu$ sh
\[\e[31m\]\u\[\e[m\]$ echo $SHELL
/bin/bash
\[\e[31m\]\u\[\e[m\]$ echo $0
sh
\[\e[31m\]\u\[\e[m\]$
Regards!
I have a RHEL box (bash) and I have SSH'd to an ESXi (sh) from it.
Now on ESXi I have created a simple script
#!/bin/sh
echo hello
exit
This only exits the script. I want to exit the script + exit the ESXi shell and return to my original RHEL bash.
Thanks much.
If you are only SSHing in for the purpose of running this command, then instead you could just have the ssh run the command for you:
[RHEL]$ ssh user#ESXi '/tmp/myscript.sh'
...and if you needed to interact with the script, or watch it's output, add the -t switch:
[RHEL]$ ssh -t user#ESXi '/tmp/mysctipt.sh'
Remove the shebang ie do
echo hello && exit
save it as script and then source the script like
. script
My default shell is bash. I have set some environment variables in my .bashrc file.
I installed a program which use .cshrc file. It contains the path to several cshell scripts.
When I run the following commands in the shell windows it works perfectly :
exec csh
source .cshrc
exec bash
I have tried to put these commands in bash script, unfortunately it didn't work.
is there another way to write a script in order to get the same result as running commands from a shell windows.
I hope my question is now clear
Many thanks for any help
WARNING : don't put the following script in your .bashrc, it will reload bash and so reload .bashrc again and again (stopable with C-c anyway)
Use preferable this script in your kit/CDS stuff startup script. (cadence presumably)
WARNING 2 : if anything in your file2source fails, the whole 'trick' stops.
Call this script : cshWrapper.csh
#! /bin/csh
# to launch using
# exec cshWrapper.csh file2source.sh
source $1
exec $SHELL -i
and launch it using
exec ./cshWrapper.csh file2source.sh
it will : launch csh, source your file and came back to the same parrent bash shell
Example :
$> ps
PID TTY TIME CMD
7065 pts/0 00:00:02 bash
$>exec ./cshWrapper.csh toggle.csh
file sourced
1
$> echo $$
7065
where in my case i use the file toggle.csh
#! /bin/csh
# source ./toggle.csh
if ! $?TOGGLE then
setenv TOGGLE 0
endif
if ($?TOGGLE) then
echo 'file sourced'
if ($TOGGLE == 0) then
setenv TOGGLE 1
else
setenv TOGGLE 0
endif
endif
echo $TOGGLE
Hope it helps
New proposal, since I faced another problem with exec.
exec kills whatever remains in the script, except if you force a fork by using a pipe after it `exec script |cat'. In such case if you have environment variable in the script, they are not spread back to the script itself, which is not what we want. The only solution I found is to use 3 files (let's call them for the example : main.bash that call first.cshrc and second.sh).
#! /bin/bash
#_main.bash_
exec /bin/csh -c "source /path_to_file/cshrc; exec /bin/bash -i -c /path_to_file/second.sh"
# after exec nothing remains (like Attila the Hun)
# the rest of the script is in 'second.sh'
With that manner, i can launch in a single script call, an old cshrc design kit, and still process some bash command after, and finally launch the main program in bash (let say virtuoso)
Is it possible to source a .bshrc file from .cshrc in a non-interactive session?
I'm asking because tcsh is our default shell at work and the .cshrc has to be used to set up the environment initially.
However, I am not really familiar with the tcsh and I have my own set-up in bash, so right now I have the following lines at the end of my .cshrc file:
if ( $?prompt && -x /bin/bash) then
exec /bin/bash
endif
This works fine, loading my environment from .bashrc and giving me a bash prompt for interactive sessions but now I also need the same set-up for non-interactive sessions, e.g. to run a command remotely via SSH with all the correct PATHs etc.
I can't use 'exec' in that case but I can't figure out how to switch to bash and load the bash config files "non-interactively".
All our machines share the same home directory, so any changes to my local *rc files will affect the remote machiens as well.
Any ideas welcome - thank you for your help!
After some more research I'm now quite sure that this won't work, but of course feel free to prove me wrong!
To load the environment in bash I have to switch to a bash shell. Even if that is possible "in the background", i.e. without getting a prompt, it would still break any tcsh commands which would then be attempted to execute under bash.
Hmmmm, back to the drawing board...
If $command is set there are arguments to csh, so it is a remote shell command. This works for me in .cshrc:
if ($?command) then
echo Executing non-interactive command in bash: $command $*
exec /bin/bash -c "${command} $*"
endif
echo Interactive bash shell
exec bash -l
Test:
$ ssh remotehost set | grep BASH
BASH=/bin/bash
...
proves that it ran in Bash.