I am having problems expanding environment variables in a service file.
This test serivice illustrates the problem:
root@yoga:/etc/systemd/system# cat varexp.service
[Unit]
Description = Test environment variable expansion
[Service]
Type = oneshot
Environment = "VAR=abc-xyz"
ExecStart = sh -c 'echo Res: ${VAR#abc-}'
Running it yields the following result:
root@yoga:/etc/systemd/system# systemctl status varexp.service
○ varexp.service - Test environment variable expansion
Loaded: loaded (/etc/systemd/system/varexp.service; static)
Drop-In: /usr/lib/systemd/system/service.d
└─10-timeout-abort.conf
Active: inactive (dead)
Sep 06 10:17:16 yoga systemd[1]: Starting varexp.service - Test
environment variable expansion...
Sep 06 10:17:16 yoga (sh)[8541]: varexp.service: Invalid environment
variable name evaluates to an empty string: VAR#abc-
Sep 06 10:17:16 yoga sh[8541]: Res:
Sep 06 10:17:16 yoga systemd[1]: varexp.service: Deactivated successfully.
Sep 06 10:17:16 yoga systemd[1]: Finished varexp.service - Test
environment variable expansion.
According to the output lines above, it is the shell that complains.
However, running the command from an interactive shell yields the
expected result:
root@yoga:/etc/systemd/system# VAR='abc-xyz' sh -c 'echo ${VAR#abc-}'
xyz
What is wrong here?
