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Ezos
Ezos

Reputation: 117

Bash Non-Sense - Variable Not Passing Correctly

When I echo out the file and when I put the name in the command directly, it works fine, but when I run it with the file name as a variable. It gives me a BAD vs a GOOD. this is obviously a shorter equation to the longer one I am trying ot get to work, but I feel if I can get this to work, then I am good.

Anyone? Any Ideas why it gives me a BAD for this?

if [ -f /home/publish/swift/$TAR_FILE ]; then echo "good"; else echo "bad"; fi

But a GOOD when I use:

if [ -f /home/publish/swift/swift_tar_1212.tgz ]; then echo "good"; else echo "bad"; fi

Upvotes: 0

Views: 84

Answers (3)

Ezos
Ezos

Reputation: 117

This problem eluded me for a few days and I knew something was weird with the string return form the other server. I have added the code that ended up working for me.

GOAL: ssh into other server, run a command in a certain directory to determine the most recent updated .tgz, then take the name of that file and pass it into a variable so that it could be run from the current instance to SCP over. Code is below

#SSH into the master prod machine and find the latest TAR.
TARFILE="$(ssh -i cross-key -t login@server  'bash -c "cd /home/publish/swift; find *.tgz -type f | xargs ls -t"')"

#Telling us the latest .tgz of Swift Website
echo "TAR List:$TARFILE"

#Pass the List into an Array and then Get the first one which is the latest .tgz file
IFS=' ' read -a array <<< "$TARFILE"
TAR_FILE "${array[0]}"

This finally gave me the string that I needed to continue with my if and else statement.

if [ -f /home/publish/swift/$TAR_FILE ]; then echo "good"; else echo "bad"; fi

And I was able to get good - therefore I could continue with the execution of the new tgz file. I had to pass the full list into an array vs just taking the last value with:

$(find *.tgz -type f | xargs ls | tail -n 1)

What a freakin nightmare. But now it works! I just hope this can help someone else that beats their head against the wall about this problem.

Upvotes: 0

lx42.de
lx42.de

Reputation: 428

If you set the TAR_FILE to the same value, then it should work

TAR_FILE='swift_tar_1212.tgz'

And please do yourself a favor and ALWAYS put the string into quotes:

if [ -f "/home/publish/swift/$TAR_FILE" ]; then echo "good"; else echo "bad"; fi

Single quotes, if you do not want an $... expansion.

Maybe you will find it useful to set xtrace:

set -x

turning it off with

set +x

If you want to glob for all files in a dir, without knowing their name:

for file in /home/publish/swift/*; do
    test -f "$file" && echo "$file"
done

All files is not perfectly correct, the hidden files are not matched this way!

for file in /home/publish/swift/{.*,*}; do
    test -f "$file" && echo "$file"
done

As @mklement0 noted, you may use shopt to modify the globbing => http://www.gnu.org/software/bash/manual/html_node/The-Shopt-Builtin.html In your case the following options may help you:

dotglob
extglob
failglob
globstar
nocaseglob
nocasematch (``[[ ]]`` only)
nullglob (very useful)

It can be confusing to set these values in your .bashrc, because a lot of examples in the web are based upon the default values. Unfortunately shopt cannot be restricted to a shell function - thats pain.

Upvotes: 3

midori
midori

Reputation: 4837

Try like this

if [ -f "/home/publish/swift/$TAR_FILE" ]
then 
    echo "good"
else 
    echo "bad"
fi

Upvotes: 1

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