Determine if file location is an alias in bash scripting

Symlinks are different than aliases, although they seem to serve the same purpose (more or less/I think). I need to be able to tell if a file is an alias, and

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if [ -h /path/to/file ]

doesn't work. Is there anything like this for aliases? Google was most unhelpful as aliases are apparently the name for something else in bash altogether.

Thanks!

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The Finder stores the information that a file is an alias in the ResourceFork of the file. To read this metadata, I would use spotlight to determine the kind of the file; the following command will return the kind of the file, so you could then compare it in an if-statement.

 mdls -raw -name kMDItemKind /path/to/test.pdf          returns  PDF (Portable Document Format)
 mdls -raw -name kMDItemKind /path/to/test.pdf\ Alias   returns  Alias

An other way would incorporate Applescript, which is executable on the command line via osascript. To return the kind of a file, run:

tell application "Finder" to get kind of ((POSIX file "/path/to/test.pdf\ Alias") as alias)

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I'm not quite clear if you're asking about:

• aliases (a way of making one command actually run something else)
• symlink (a way of making a shortcut to a file)
• hard link (two file names both pointing to the same file contents)

The command you were trying:

if [ -h /path/to/file ]

helps you figure out if a file is a symlink or not, e.g.:

$ touch newfile
$ ln -s newfile newlink
$ for f in newfile newlink; do
    if [ -h "$f" ]; then
        echo "$f is a symlink"
    else
        echo "$f is not a symlink"
    fi
done
newfile is not a symlink
newlink is a symlink

If you mean: "how can I find out whether typing some command will run an alias", then you can use type or alias, e.g.

$ type ls
ls is aliased to `ls --color=auto --format=across'

$ type less
less is /usr/bin/less

If you're asking about hard links, find -inum and ls -i can help, but that is a more advanced topic.

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Asmus' solution did not quite work for me, but he got me started. Here is what worked for me (macOS 10.13 , High Sierra, assuming you execute it in bash):

alias=$( mdls -name kMDItemKind "$file" )
if [[ "$alias" = *Alias* ]]
then
    echo "$file is an Alias"
fi

HTH.

---

You could use the /usr/bin/getfileinfo utility:

if ((`getfileinfo -aa /path/to/file`))
then #
fi