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# 1  
Old 10-10-2007
Nested If question

if [[ -a ${LOGFILE} ]]; then
if [[ -a ${LOGFILE}.old ]]; then
rm -f ${LOGFILE}.old
fi
mv ${LOGFILE} ${LOGFILE}.old
fi

Havent done nested ifs in a while. I'm reading someones code If I'm reading this correctly. It checks for the logfile, and if it exists it checks for the old logfile and if that exists, it removes the old log file. Else it moves the logfile to the logfile.old. Someone correct me if I'm wrong, thanks.
# 2  
Old 10-10-2007
You have it right. Except the -a should maybe be a -f because -a means "and" which makes no sense in what you posted
# 3  
Old 10-10-2007
Quote:
Originally Posted by jim mcnamara
You have it right. Except the -a should maybe be a -f because -a means "and" which makes no sense in what you posted
Not my code, just a copy and paste. But I was wondering what the -a meant. I guess the -f means file. Thanks.
# 4  
Old 10-10-2007
See the man page for test -- man test
it has all of those -<whatever> tests and tells you their meaning. -f tells you if it is a regular file and exists, for example.
# 5  
Old 10-10-2007
Quote:
Originally Posted by NycUnxer
if [[ -a ${LOGFILE} ]]; then
if [[ -a ${LOGFILE}.old ]]; then
rm -f ${LOGFILE}.old
fi
mv ${LOGFILE} ${LOGFILE}.old
fi

Havent done nested ifs in a while. I'm reading someones code If I'm reading this correctly. It checks for the logfile, and if it exists it checks for the old logfile and if that exists, it removes the old log file. Else it moves the logfile to the logfile.old. Someone correct me if I'm wrong, thanks.
not exactly - it will 'move the logfile to the logfile.old' regardLESS whether the 'old logfile' exists or not - there is no 'ELSE' in the inner 'if'.

Last edited by vgersh99; 10-10-2007 at 06:39 PM..
# 6  
Old 10-10-2007
Then this makes less sense. Wouldnt the move overwrite whats there if the old one exists anyway? I dont see the reason for the remove then.
# 7  
Old 10-10-2007
what about this- is this what u r looking for?

if [[ -s ${LOGFILE} ]] && [[ [[ -s ${LOGFILE}.old ]]; then
rm -f ${LOGFILE}.old
mv ${LOGFILE} ${LOGFILE}.old
fi


cheers,
Devaraj Takhellambam
 

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