This is probably a very simple thing but I can’t find an answer, possibly because I don’t know what terms to use in search.

How do I use an alias of a path with mv or cp? Or even cd?

In /etc/bash.bashrc I have: alias docs=‘/media/docs

cd docs Gives “No such file or directory”

Yet: docs Gives “Is directory”

With alias docs=‘cd /media/docs’ and by typing docs I get into the directory. Obviously I can’t use that alias with mv or cp though.

Maybe this isn’t even an intended use of alias but still. Why doesn’t it work?

  • darklamer@feddit.org
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    11 hours ago

    As already pointed out in other comments here, alias is used specifically to define a new shell command and in order to define some arbitrary text substitution to be used anywhere in a commandline you’ll need to use a variable instead, but for the specific case of cd there’s also a feature called CDPATH that you might be interested in learning about:

    https://writesoftwarewell.com/cdpath-easily-navigate-directories-in-the-terminal

  • davel@lemmy.ml
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    19 hours ago

    alias is for aliasing commands. If you want to “alias“ arguments, use shell/environment variables.

    $ docs=/media/docs
    $ cd $docs
    
    • teawrecks@sopuli.xyz
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      16 hours ago

      It is worth acknowledging that this probably seems unintuitive to a new user. Makes it look like the shell has two different aliasing systems.

      It makes sense the more familiar you are with bash, though. If you ever tried to cd /some/other/path-with-docs/in/the/string you’d end up accidentally running cd /some/other/path-with-/media/docs/in/the/string.

      Which would be confusing at best, or a security issue at worst. Better to see that $ in the cmd and know you’re injecting a var’s value.

  • rycee@lemmy.world
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    16 hours ago

    It might be excessive for your purposes but an alternative may be to use zoxide. It learns the directories you use regularly and you can then cd to those directories through the z command. E.g. z docs.

  • MimicJar@lemmy.world
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    18 hours ago

    You might find a symbolic link useful. For example

    ln -s /media/docs ~/docs
    

    Now you’ll have a “folder” in your home directory named “docs” that points to “/media/docs”. You can use that path with commands like mv or cp.

    These commands now both move “myfile” to the same location

    mv myfile ~/docs
    mv myfile /media/docs
    
    • MolochHorridus@piefed.socialOP
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      18 hours ago

      Thanks, but the problem with this is that I’ll type /media/docs/whatever much faster than hunt the ~ from my keyboard because I have to move my whole hand to do so.

      It’s altGr + ^ on my keyboard.

      • teawrecks@sopuli.xyz
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        16 hours ago

        Highly recommend remapping common characters to easy-to-access hand movements. The keyboard is a tool to make things easier. I never use caps-lock, but I use esc all the time, so I regularly swap them (or just have a second esc bind).

      • False@lemmy.world
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        17 hours ago

        That sounds inconvenient. I use ~ all the time. $HOME should point to the same dir in most cases though

  • TwistedTree@piefed.social
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    18 hours ago

    You should be using a variable not an alias.

    Variables in bash have a few sharp edges; one of which is that spaces act as a delimiter and turn the variable into a list.

    The other being that sometimes escaping and unescaping the contents of a variable can be stupidly tricky. This is why a lot of people who use bash do not like spaces in directory or file names.

    • MolochHorridus@piefed.socialOP
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      18 hours ago

      Thanks for the tip, but escaping and unescaping sounds tedious, since I use spaces in both directory and file names.

      What I like about aliases here is that I have one central location to set them up and change them. If I ever were to forget what aliases I have it’s just about opening the file and looking.

      • TwistedTree@piefed.social
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        17 hours ago

        eh, it’s mostly automagic but the first few times you encounter it makes for some fun debugging.

        Play around with the var=$(ls -A) construction a bit and see what is happening with your files.

  • brandon@piefed.social
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    18 hours ago

    By default bash will only expand an alias if it’s the first argument of the command (that is, the command itself).

    It’s probably not intended to use aliases this way, and there are probably better options for you.

    However, there is a little trick you can do. If the alias command ends in a space, then bash will also check the next argument:

    alias cd='cd '

    Notice the trailing space after ‘cd’ in the alias definition.

    alias docs='/media/docs'

    then, cd docs should work the way you expect.

    Another method would be to:

    alias docs='echo /media/docs'

    Then you can do

    cd `docs`  
    

    The backticks will cause the shell to replace that portion with the output of the docs shell command, which will be expanded via the alias.

    All that said, it’s probably easiest just to use a link, like another commenter suggested.

  • alastel@lemmy.ml
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    16 hours ago

    You might consider looking into other shells. Fish has things such as nor requiring escaping variables with spaces and defining abbreviations that can work anywhere in a command line.

  • just_another_person@lemmy.world
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    19 hours ago

    This is a bad idea for a number of reasons. Instead, if you move files to a specific location frequently, you want to make a symbolic link to that location instead. It acts as a circuit breaker in case something about your environment changes or breaks.