I use a script, test.sh
, written by someone else, the begins with a bash shebang:
#!/bin/bash -l
...
echo TEST: $TEST
From what I could see, this has an effect on variables used inside the script:
- if I run
TEST=hey ./test.sh
, I can seeTEST: hop
,hop
being the value of variableTEST
in my.bash_profile
- this is the same if I
export TEST=hey
before running the script - but if I remove the
-l
flag, the same command returnsTEST: hey
, as I would have expected
Can someone please explain this behaviour ? The help of bash did not... help.
The
-l
option (according to the man page) makes "bash act as if it had been invoked as a login shell". Login shells read certain initialization files from your home directory, such as.bash_profile
. Since you set the value ofTEST
in your.bash_profile
, the value you set on the command line gets overridden whenbash
launches.