[Unit]
Description=Test for StandardOutput=file:

[Service]
ExecStartPre=sh -c 'printf "nooo\nhello\n" >/tmp/test-exec-standardoutput-output'
ExecStartPre=sh -c 'printf "hello\nello\n" >/tmp/test-exec-standardoutput-expected'
StandardInput=data
StandardInputText=hello
StandardOutput=file:/tmp/test-exec-standardoutput-output
StandardError=null
ExecStart=cat
ExecStart=cmp /tmp/test-exec-standardoutput-expected /tmp/test-exec-standardoutput-output
Type=oneshot
