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🔍 See Original Question on Ask Ubuntu ⧉ 🔗
URL:
https://askubuntu.com/q/1168750
Title:
How to pass 2>/dev/null as a variable?
ID:
/2019/08/27/How-to-pass-2__dev_null-as-a-variable_
Created:
August 27, 2019
Edited: August 28, 2019
Upload:
October 19, 2025
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I have this code that works:
# Hide irrelevant errors so chrome doesn't email us in cron
if [[ $fCron == true ]] ; then
google-chrome --headless --disable-gpu --dump-dom \
"$RobWebAddress" > "$DownloadName" 2>/dev/null
else
# Get silly error messages when running from terminal
google-chrome --headless --disable-gpu --dump-dom \
"$RobWebAddress" > "$DownloadName"
fi
If I try to shorten it like this:
# Hide irrelevant errors so chrome doesn't email us in cron
local HideErrors
[[ $fCron == true ]] && HideErrors="2>/dev/null"
google-chrome --headless --disable-gpu --dump-dom \
"$RobWebAddress" > "$DownloadName" "$HideErrors"
I get error messages:
[0826/043058.634775:ERROR:headless_shell.cc(597)] Open multiple tabs is only supported when remote debugging is enabled.
[0826/043058.672587:ERROR:headless_shell.cc(597)] Open multiple tabs is only supported when remote debugging is enabled.
[0826/043058.711640:ERROR:headless_shell.cc(597)] Open multiple tabs is only supported when remote debugging is enabled.
(... SNIP ...)
Why does a hard-coded argument work but not an argument as a variable?
Edit 2:
Currently I found success with second answer’s alternate suggestion:
# Redirect errors when cron is used to /dev/null to reduce emails
ErrorPipe=/dev/stderr
[[ $fCron == true ]] && ErrorPipe=/dev/null
google-chrome --headless --disable-gpu --dump-dom \
"$RobWebAddress" > "$DownloadName" 2>"$ErrorPipe"
## ```
### Edit 1:
Based on the first answer, I should point out program header already contains:
``` bash
[[ $fCron != true ]] &&
exec 2> >(grep -v 'GtkDialog mapped without a transient parent' >&2)