lp command doesn't run as cron job (according to no log entry

Question

I need to run this lp command periodically:

lp /Users/denniscook/Documents/PrinterManagement/UseInk.pdf 2>&1 >>/Users/denniscook/.cronlogs/runPrinter.log

I have this command in runPrinter.zsh script:

#!/usr/bin/env zsh

cat >>/Users/denniscook/.cronlogs/runPrinter.log <<EOF

***************************
Enter Job `date`
EOF

lp /Users/denniscook/Documents/PrinterManagement/UseInk.pdf 2>&1 >>/Users/denniscook/.cronlogs/runPrinter.log

cat >> /Users/denniscook/.cronlogs/runPrinter.log <<EOF
Exit Job `date`

EOF

The lp command is executed correctly when directly issued in terminal, or when the script is issued in terminal- meaning printer prints and log gets updated. But when either the command or the script is run from cron, neither works.

In crontab, I have tried two approaches using the crontab below, commenting out one entry and using the other. The first will run the script, the second attempts to run the command directly.

#-----------#
# cron jobs #
#-----------#
#06 11 * * * /Users/denniscook/.scripts/runPrinter.zsh
13 11 * * * lp /Users/denniscook/Documents/PrinterManagement/UseInk.pdf 2>&1 >>/Users/denniscook/.cronlogs/runPrinter.log

~                                                                                                                                       
~                                                                                                                                       

When script is executed from terminal, and it works correctly, log entry is:

***************************
Enter Job Sun Jan 29 11:07:26 HST 2023
request id is EPSON_WorkForce_845-1286 (1 file(s))
Exit Job Sun Jan 29 11:07:26 HST 2023

When cron executes the script, the log entry is as follows (no output from lp cmd):

***************************
Enter Job Sun Jan 29 12:15:00 HST 2023
Exit Job Sun Jan 29 12:15:00 HST 2023

When cron executes lp command directly,there is no log entry.

I don't know what difference there is between cron executing the job, and my executing them in terminal. My research failed to find an answer.

I appreciate any help...

Answer 1

The problem is that the cron process doesn't have full disk access.

Solution:

• Go to Settings > Security & Privacy then select "Full Disk Access" in the list on the left.
• Click the plus button to add a new app.
• In the file browser type a forward slash to switch into direct entry mode. Enter the path /usr/sbin/cron. (found it by typing 'which cron' on the terminal)

Alternatively use Automator instead of cron. (If you want to learn a new tool, but that sounds annoying...)

(This answer was in the comments, and I'm just posting it here as a formal answer so the next person doesn't have to read all the comments to get the answer. Thanks for gpaCook for sharing the final solution.)