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explanation for "if [ -s $filename ];"

 
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Top Forums UNIX for Dummies Questions & Answers explanation for "if [ -s $filename ];"
# 1  
Old 12-14-2007
CPU & Memory explanation for "if [ -s $filename ];"
Hi all,

Can any one explain me what the below 'if' statement checking for?

if [ ! -s $filename]; then
do something
fi

Iam aware of the remaining options like -z, -r, -w, -x etc., with 'if' statement, but I dont know about '-s' Smilie.

Thanks in advance,
Mysore 101 Ganapati.
# 2  
Old 12-14-2007
Quote:
Originally Posted by ganapati
Hi all,

Can any one explain me what the below 'if' statement checking for?

if [ ! -s $filename]; then
do something
fi

Iam aware of the remaining options like -z, -r, -w, -x etc., with 'if' statement, but I dont know about '-s' Smilie.

Thanks in advance,
Mysore 101 Ganapati.
That means if !(file exists and not empty) Smilie
Im pretty sure you did know that Smilie
Last edited by andryk; 12-14-2007 at 07:41 AM..
# 3  
Old 12-14-2007
On google, enter the search "man test".
You never know what new options you'll find (I just found out that -S tests for a socket)!
# 4  
Old 05-06-2009
MySQL Nidhin
-s is used to check the file size is 0 or not..Smilie
# 5  
Old 08-20-2009
-s = file exists AND not zero bytes
 
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