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Conditional OR in shell

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# 1  
Old 04-25-2016
Conditional OR in shell
Hi

I have been trying to write a simple code:

Code:
if [[ `(ls -A $apache_log_dir | egrep *.log)` ]] || [[ `(ls -A $jboss_log_dir | egrep *.log)` ]]
then
echo "Log Directory is not empty, we will continue with archive operation"
else
echo "Log Directory is empty, Exiting......."
exit 1
fi

It never checks for the second OR condition i.e.
Code:
 [[ `(ls -A $jboss_log_dir | egrep *.log)` ]]

Could you please help?

Thanks
# 2  
Old 04-25-2016
If the result is true for the first test, the second test will not be executed due to "short circuit evaluation".

The egrep seems redundant, what do you expect it to do what a ls *.log would not deliver? And it may not yield what you're after: it would show e.g. alogin as well.
This User Gave Thanks to RudiC For This Post:
ankur328
# 3  
Old 04-25-2016
Hi Rudi,

Yes you are correct. Any way to check both the conditions?

Also *.log are the on;ly files present in the folders, so I am fail safe in this egrep.

Thanks
# 4  
Old 04-25-2016
Try
Code:
if [[ $(ls -A $apache_log_dir/*.log $jboss_log_dir/*.log) ]]

It will check in both directories for .log files and evaluate to true if a file exists in either.
This User Gave Thanks to RudiC For This Post:
ankur328
# 5  
Old 04-25-2016
thats brilliant Rudy, Many thanks...
# 6  
Old 04-25-2016
Quote:
Originally Posted by RudiC
Try
Code:
if [[ $(ls -A $apache_log_dir/*.log $jboss_log_dir/*.log) ]]

It will check in both directories for .log files and evaluate to true if a file exists in either.
Note that if either of those directories are empty, or at least do not contain any files with names ending in .log, the command substitution will print a diagnostic message. You can avoid having those appear on the screen when you run this script by throwing away any diagnostics produced by ls:
Code:
if [[ $(ls -A $apache_log_dir/*.log $jboss_log_dir/*.log 2>/dev/null) ]]

This User Gave Thanks to Don Cragun For This Post:
ankur328
# 7  
Old 04-25-2016
This could be simplified further still:
Code:
if ls -A "$apache_log_dir"/*.log "$jboss_log_dir"/*.log 1>/dev/null 2>&1; then

Last edited by Scrutinizer; 04-25-2016 at 07:38 AM..
This User Gave Thanks to Scrutinizer For This Post:
ankur328
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