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How to check if a symlink exists

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bash

symlink

People also ask

How do I know if a symlink is working?

Your Bash script might need to determine if a file is a symlink or not. In Bash you can test this with the -L operator that returns true if the file exists and is a symlink.

How do you check if a symlink is broken?

3. Finding Broken Symlinks. The -H, -L and -P options control how symbolic links are treated, and when omitted, use -P as the default. When -P is used and find examines or prints information from a symbolic link, the details are taken from the properties of the symbolic link itself.

How do I find my target symbolic link?

The Symlink option (Symlink Target Operations) only appears in the context menu from ClearCase Explorer after right-clicking on an actual symbolic link. If the symlink target is in another VOB, then that VOB must also be mounted on the local system.


-L returns true if the "file" exists and is a symbolic link (the linked file may or may not exist). You want -f (returns true if file exists and is a regular file) or maybe just -e (returns true if file exists regardless of type).

According to the GNU manpage, -h is identical to -L, but according to the BSD manpage, it should not be used:

-h file True if file exists and is a symbolic link. This operator is retained for compatibility with previous versions of this program. Do not rely on its existence; use -L instead.


You can check the existence of a symlink and that it is not broken with:

[ -L ${my_link} ] && [ -e ${my_link} ]

So, the complete solution is:

if [ -L ${my_link} ] ; then
   if [ -e ${my_link} ] ; then
      echo "Good link"
   else
      echo "Broken link"
   fi
elif [ -e ${my_link} ] ; then
   echo "Not a link"
else
   echo "Missing"
fi

-L tests whether there is a symlink, broken or not. By combining with -e you can test whether the link is valid (links to a directory or file), not just whether it exists.


-L is the test for file exists and is also a symbolic link

If you do not want to test for the file being a symbolic link, but just test to see if it exists regardless of type (file, directory, socket etc) then use -e

So if file is really file and not just a symbolic link you can do all these tests and get an exit status whose value indicates the error condition.

if [ ! \( -e "${file}" \) ]
then
     echo "%ERROR: file ${file} does not exist!" >&2
     exit 1
elif [ ! \( -f "${file}" \) ]
then
     echo "%ERROR: ${file} is not a file!" >&2
     exit 2
elif [ ! \( -r "${file}" \) ]
then
     echo "%ERROR: file ${file} is not readable!" >&2
     exit 3
elif [ ! \( -s "${file}" \) ]
then
     echo "%ERROR: file ${file} is empty!" >&2
     exit 4
fi

Maybe this is what you are looking for. To check if a file exist and is not a link.

Try this command:

file="/usr/mda" 
[ -f $file ] && [ ! -L $file ] && echo "$file exists and is not a symlink"

How about using readlink?

# if symlink, readlink returns not empty string (the symlink target)
# if string is not empty, test exits w/ 0 (normal)
#
# if non symlink, readlink returns empty string
# if string is empty, test exits w/ 1 (error)
simlink? () {
  test "$(readlink "${1}")";
}

FILE=/usr/mda

if simlink? "${FILE}"; then
  echo $FILE is a symlink
else
  echo $FILE is not a symlink
fi

  1. first you can do with this style:

    mda="/usr/mda"
    if [ ! -L "${mda}" ]; then
      echo "=> File doesn't exist"
    fi
    
  2. if you want to do it in more advanced style you can write it like below:

    #!/bin/bash
    mda="$1"
    if [ -e "$1" ]; then
        if [ ! -L "$1" ]
        then
            echo "you entry is not symlink"
        else
            echo "your entry is symlink"
        fi
    else
      echo "=> File doesn't exist"
    fi
    

the result of above is like:

root@linux:~# ./sym.sh /etc/passwd
you entry is not symlink
root@linux:~# ./sym.sh /usr/mda 
your entry is symlink
root@linux:~# ./sym.sh 
=> File doesn't exist

Is the file really a symbolic link? If not, the usual test for existence is -r or -e.

See man test.