I run the following script:

sh -c 'echo "Hello $VAR"'

But I get :

# ./test.sh

How can I send the variable VAR of my script to the shell created with sh -c '...'?


Either use export to turn it into an environment variable, or pass it directly to the command.

VAR="Test" sh -c 'echo "Hello $VAR"'

export VAR
sh -c 'echo "Hello $VAR"'

Avoid using double quotes around the shell code to allow interpolation as that introduces command injection vulnerabilities like in:

sh -c " echo 'Hello $VAR' "

causing a reboot if called when $VAR contains something like ';reboot #

  • Not really practical (I have several variables, and I don't want them to be environment variables), but it works, thanks! – Matthieu Napoli Oct 24 '11 at 8:41
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    @Matthieu: They are only set as environment variables for the children of your process, if that's what worries you. – Piskvor Oct 24 '11 at 12:47
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    Just FYI, You can also do export var="Test" in one line. – user606723 Oct 24 '11 at 14:16
  • @Piskvor well thank you for the precision, that's perfect then. – Matthieu Napoli Oct 25 '11 at 7:50

Here's yet another way to pass variables to sh -c (as positional arguments):

sh -c 'echo "Hello ${0}${1}"' "$VAR" "$VAR2"
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    (+1) To keep it more in line with the normal $1 $2 expectation for script variables, it can have a dummy value for $0. This will allow $@ to work as expected, eg. sh -c 'echo "Hello $@"' _ "$VAR" "$VAR2" ` – Peter.O Oct 24 '11 at 16:09
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    @Peter.O Rather than using "_", I would use "sh" or a sensible name to give to that command, since that $0 is displayed in the error/warning messages by the shell. – Stéphane Chazelas Jan 26 '13 at 21:45

If you don't want to export them as environment variables, here's a trick you could do. Save your variabe definition to a file .var_init.sh and source it in your sub-shell like this:



from the command line:

sh -c ". .var_init.sh && echo \$VAR" # Make sure to properly escape the '$'

This way, you only set your variables at the execution of your subshell.

  • ... or ENV=.var_ini.sh sh -c '...' – Kusalananda May 7 '18 at 9:47
  • Note that if that .var_init.sh is expected to be looked for in the current directory (as opposed to $PATH), it should be written . ./var_init.sh – Stéphane Chazelas Aug 31 at 12:58

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