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I need to do a script to look in some folders and send an email if there are files in these folders.
I've tried to do something like this but I get errors with the command variable and print of the folder.

for folder in "FOLDER1" "FOLDER2";  do
  command=`ssh -q user@host "ls /usr/local/username/`{print $folder}` | wc -l"`
  #echo $command

  if [ $command -ne '0' ]
    #send error email 
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up vote 2 down vote accepted

You should try with:

command=$(ssh -q user@host 'ls "/usr/local/username/'$folder'" | wc -l')

You can't really nest backticks (and I'm not sure why you wanted to to that anyway).

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it works! thanks a lot – simone May 17 '12 at 10:21

This can be a lot simpler. I have no idea what you're tring to do with {print $folder}: the braces don't make any sense here, and if you're trying to include $folder in the string, you would just write $folder. You should not parse the output of ls, it's very rarely useful and often fails.

if ! ssh user@host "test -e '/usr/local/username/$folder'"; then
  # the file doesn't exist

Note that the file name must be quoted for the remote shell. I mostly took care of this in my command above, by surrounding the file name in the remote command with single quotes, but that only works if $folder itself does not contain any single quotes. If your local shell is bash, ksh93 or zsh, use this instead, to quote any single quote:

if ! ssh user@host "[ -d '/usr/local/username/${folder//\'/$q}' ]"; then

Another approach which is usually more convenient is to mount the remote filesystem with sshfs and work on it through the normal filesystem interface. I recommend this unless you're working with a lot of remote servers at the same time.

mkdir /path/to/mount/point
sshfs user@host /path/to/mount/point
if ! [ -d "/usr/local/username/$folder" ]; then
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