Assigning the output of the "at" command in a bash script

Question

I'm trying to capture the results of the "at" command inside a Bash script. The various ways of capturing command output don't seem to work, but I'm not sure if it's the pipe in the command or something else.

echo $cmd | at $deployat

produces the output

job 42 at 2014-04-03 12:00

And I'm trying to get at the time the job was set for.

However, I expected something like

v=$($cmd | at $deployat)
echo $v

Would work, or

v=$(echo $cmd | at $deployat)
echo $v

Or

v=`$cmd | at $deployat`
echo $v

But all of those leave the script hung, looking like it's waiting for some input.

What is the proper way to do this to end up with a variable like:

2014-04-03 12:00

============================

Edit:

One possible complication is that the $cmd has flags with it:

ls -l

for example.

The expanded command could be something like:

echo ls -l | at noon tomorrow

Solution:

v=$(echo $cmd | at $deployat 2>&1)
echo $v

The command out=$(echo ls -l | at -v 2014-04-03 2>&1 | head -n 1) works fine for me... — Stephan Kulla
– Stephan Kulla, Commented Apr 2, 2014 at 23:33

Stephan Kulla · Accepted Answer · 2014-04-02 23:18:21Z

3

at prints its output to stderr not stdout. Use 2>&1 to pipe the stderr of at into stdout. Example:

~$ out=$(echo cat Hello | at -v 2014-04-03 2>&1 | head -n 1)
~$ echo $out
Thu Apr 3 01:21:00 2014

With -v it prints the execution time on the first line which is taken by head -n 1.

answered Apr 2, 2014 at 23:18

Stephan Kulla

5,1273 gold badges28 silver badges35 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Teg Ryan Over a year ago

I get the following error when I try this: ./deploy: line 121: =job: command not found

Stephan Kulla Over a year ago

How does your deploy file look like? (The lines around line number 121)

Teg Ryan Over a year ago

I accidentally wrote $v=... in your solution, when changed to "v=..." it works. Thanks!!

Collectives™ on Stack Overflow

Assigning the output of the "at" command in a bash script

Edit:

Solution:

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

Edit:

Solution:

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related