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[Solved] Problem bash if file exists then < do...> else <do...>

 
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# 1  
Old 05-27-2013
[Solved] Problem bash if file exists then < do...> else <do...>
Hi !

I have a problem with an if/else statement in bash.
I want to check if the file exists before running a task (for example here, counting lines), and if not I need to create an empty output file
Code:
if [ -f /input.tab ]
then
wc -l input.tab > output.temp
else
>output.temp
fi

The problem is even if the condition is true (the file actually exists) it goes directly to the else part and create an empty file in any case.

Could someone explain me what is wrong with my syntax... Smilie!!!
# 2  
Old 05-27-2013
Quote:
Originally Posted by beca123456
Hi !

I have a problem with an if/else statement in bash.
I want to check if the file exists before running a task (for example here, counting lines), and if not I need to create an empty output file
Code:
if [ -f /input.tab ]
then
wc -l input.tab > output.temp
else
>output.temp
fi

The problem is even if the condition is true (the file actually exists) it goes directly to the else part and create an empty file in any case.

Could someone explain me what is wrong with my syntax... Smilie!!!
Does the file input.tab really exist in the root directory (/input.tab), or is it in the current directory (input.tab)? It would seem that you should use the same pathname in both the test and the wc commands.
This User Gave Thanks to Don Cragun For This Post:
beca123456
# 3  
Old 05-27-2013
Smilie

Thanks again Don Cragun !
 
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