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WHy the double square brackets?

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# 1  
Old 12-04-2008
WHy the double square brackets?
One of the senior administrators gave me a shell script to modify and it begins as follows:

if [[ -s valid_users.tmp ]] && [[ -s invalid_users.tmp ]]
{more code follows}

Why the double square brackets?
# 2  
Old 12-04-2008
This is the 3rd time in 3 days this same question has been asked, how about using the search?

https://www.unix.com/shell-programmin...condition.html
# 3  
Old 12-04-2008
Okay I tried.....
I read what you posted so why doesn't the following work:
Code:
if ![[ -s illegal_loggons.tmp ]] && ![[ -s illegal_loggons1.tmp ]] then
exit
fi

I am trying to say if both files have no information in then exit...Should the "!" go inside the square brackets? The interpreter does not seem to recognize ![[
# 4  
Old 12-04-2008
Yes inside.
# 5  
Old 12-04-2008
Quote:
Originally Posted by Ikon
Yes inside.
Code:
if [[ ! -s illegal_loggons.tmp  ]] && [[ ! -s illegal_loggons1.tmp  ]]
then
exit
fi

I get this from the interpreter now:

line 26: syntax error near unexpected token `fi'
./script.sh: line 26: `fi'
# 6  
Old 12-04-2008
Something wrong somewhere else in your script it seems.

Actually why are you using -s ? -e should be used.

-e file = True if the file exists.
-s file = True if the file exists and is a socket.
# 7  
Old 12-08-2008
#!/bin/ksh
if [ ! -s valid_users.tmp -a ! -s invalid_users.tmp ]
then
exit
fi
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