[Tutor] symlinking dirs with spaces

[Dave Angel]

On 04/26/2013 08:10 AM, mike wrote:
> Hi all,
>
> I wrote a cli script for syncing my music to a USB mass storage device
> like a phone etc. all it does is it creates a symlink in a dir to
> whatever folder i pass as an argument via ./addsync DIR . My problem is
> i'm having trouble dealing with directories with spaces. when using
> os.symlink I get the error below and when using subprocess it creates
> individual directories for the words separated by white space. any help
> would be appreciated on how to approach this.thanks!
>
> This is the script:
>
> #!/usr/bin/env python
> import os
> from sys import argv
> import subprocess
> script, media = argv
>
> # This is the directory you will sync the symbolic links from, to the
> device.
> loadDir = "/opt/data/music/load/"
>
> # This is the destination folder, whatever folder the device is mounted to.
> destDir = "/media/MOT_"
>
> # Get the current working directory
> origDir = os.getcwd()
>
> # Glob the current working directory and the "media" argument together
> # to form a full file path
> origFul = os.path.join('%s' % origDir, '%s' % media)
>
> linkDir = "ln -s %s %s" % (origFul, loadDir)
>
> # Command to sync if media == "push"
> syncCom = "rsync -avzL %s %s" % (loadDir, destDir)
>
> def link():
>      print "Adding %s to %s..." % (origFul, loadDir)
>      os.symlink('origFul', 'media')
> #    subprocess.call(linkDir, shell=True)

By using shell=True, you're forcing your OS's shell to interpret the 
line.  If you insist on that approach, you'll need to escape any 
embedded spaces, same as you would in the terminal.

Easier and safer would be to pass the list of argument to 
subprocess.call, the way these docs show:

    http://docs.python.org/2/library/subprocess.html#subprocess.call

So instead of linkDir looking like "ln -s file 1 file2"  it should look 
like:
     ["ln", "-s", "file 1", "file2"]
and you'd use it like:
     subprocess.call(linkDir)

Avoiding the shell=True is faster, safer, and usually much easier.



-- 
DaveA