check if file exists on remote host with ssh

Question

I would like to check if a certain file exists on the remote host. I tried this:

$ if [ ssh user@localhost -p 19999 -e /home/user/Dropbox/path/Research_and_Devel         


        

Answer 1

Here is a simple approach:

#!/bin/bash
USE_IP='-o StrictHostKeyChecking=no username@192.168.1.2'

FILE_NAME=/home/user/file.txt

SSH_PASS='sshpass -p password-for-remote-machine'

if $SSH_PASS ssh $USE_IP stat $FILE_NAME \> /dev/null 2\>\&1
            then
                    echo "File exists"
            else
                    echo "File does not exist"

fi

You need to install sshpass on your machine to work it.

Answer 2

ssh -q $HOST [[ -f $FILE_PATH ]] && echo "File exists"

The above will run the echo command on the machine you're running the ssh command from. To get the remote server to run the command:

ssh -q $HOST "[[ ! -f $FILE_PATH ]] && touch $FILE_PATH"

Answer 3

I wanted also to check if a remote file exist but with RSH. I have tried the previous solutions but they didn't work with RSH.

Finally, I did I short function which works fine:

function existRemoteFile ()
{
REMOTE=$1
FILE=$2
RESULT=$(rsh -l user $REMOTE  "test -e $FILE && echo \"0\" || echo \"1\"")
if [ $RESULT -eq 0 ]
then
    return 0
else
    return 1
fi
}

Answer 4

In addition to the answers above, there's the shorthand way to do it:

ssh -q $HOST [[ -f $FILE_PATH ]] && echo "File exists" || echo "File does not exist";

-q is quiet mode, it will suppress warnings and messages.

As @Mat mentioned, one advantage of testing like this is that you can easily swap out the -f for any test operator you like: -nt, -d, -s etc...

Test Operators: http://tldp.org/LDP/abs/html/fto.html

Answer 5

one line, proper quoting

ssh remote_host test -f "/path/to/file" && echo found || echo not found

Answer 6

You can specify the shell to be used by the remote host locally.

echo 'echo "Bash version: ${BASH_VERSION}"' | ssh -q localhost bash

And be careful to (single-)quote the variables you wish to be expanded by the remote host; otherwise variable expansion will be done by your local shell!

# example for local / remote variable expansion
{
echo "[[ $- == *i* ]] && echo 'Interactive' || echo 'Not interactive'" | 
    ssh -q localhost bash
echo '[[ $- == *i* ]] && echo "Interactive" || echo "Not interactive"' | 
    ssh -q localhost bash
}

So, to check if a certain file exists on the remote host you can do the following:

host='localhost'  # localhost as test case
file='~/.bash_history'
if `echo 'test -f '"${file}"' && exit 0 || exit 1' | ssh -q "${host}" sh`; then
#if `echo '[[ -f '"${file}"' ]] && exit 0 || exit 1' | ssh -q "${host}" bash`; then
   echo exists
else
   echo does not exist
fi