I want to define environment variables in one place which will be accessible through different user's crontabs, and from bash shell running.
How can I write it once in one place to be accessible to all usages mentioned above?
Until now I'm writing to system wide bashrc in /etc/bashrc , and in crontabs I write this again above crontab definitions
I don't think you can do this in the crontab directly. The crontab file isn't a shell script so trying to source a script containing envvars into it doesn't work
. /path/to/envvars
crontab won't install this as it's not valid
crontab: installing new crontab
"/tmp/crontab.iZqWJX/crontab":1: bad minute
errors in crontab file, can't install.
What you could try is sourcing a script containing your envvars immediately before you run our job
* * * * * . /path/to/envars ; /path/to/your/job
I tested this with
* * * * * . /home/iain/envvars ; echo $HELLO >/tmp/test.out
with the envvars file containing
HELLO=fred
the file /tmp/test.out contained the following
fred
So I guess that worked. The source command (a synonym for . ) is a bash builtin but source is not posix so using . is preferred.
help source
source: source filename [arguments]
Execute commands from a file in the current shell.
Read and execute commands from FILENAME in the current shell. The
entries in $PATH are used to find the directory containing FILENAME.
If any ARGUMENTS are supplied, they become the positional parameters
when FILENAME is executed.
Exit Status:
Returns the status of the last command executed in FILENAME; fails if
FILENAME cannot be read
