What is $PATH
?
How can I have commands/programs which are only available for me?
I have seen this path ~/bin
mentioned before, but what is it used for, and how do I use it?
What is $PATH
?
How can I have commands/programs which are only available for me?
I have seen this path ~/bin
mentioned before, but what is it used for, and how do I use it?
$PATH is an environment variable used to lookup commands. The ~ is your home directory, so ~/bin will be /home/user/bin; it is a normal directory.
When you run "ls" in a shell, for example, you actually run the /bin/ls program; the exact location may differ depending on your system configuration. This happens because /bin is in your $PATH.
To see the path and find where any particular command is located:
$ echo $PATH
/home/user/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:...
$ which ls # searches $PATH for an executable named "ls"
/bin/ls
$ ls # runs /bin/ls
bin desktop documents downloads examples.desktop music pictures ...
$ /bin/ls # can also run directly
bin desktop documents downloads examples.desktop music pictures ...
To have your own private bin directory, you only need to add it to the path. Do this by editing ~/.profile (a hidden file) to include the below lines. If the lines are commented, you only have to uncomment them; if they are already there, you're all set!
# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/bin" ]; then
PATH="$HOME/bin:$PATH"
fi
Now you need to create your ~/bin directory and, because .profile is run on login and only adds ~/bin if it exists at that time, you need to login again to see the updated PATH.
Let's test it out:
$ ln -s $(which ls) ~/bin/my-ls # symlink
$ which my-ls
/home/user/bin/my-ls
$ my-ls -l ~/bin/my-ls
lrwxrwxrwx 1 user user 7 2010-10-27 18:56 my-ls -> /bin/ls
$ my-ls # lookup through $PATH
bin desktop documents downloads examples.desktop music pictures ...
$ ~/bin/my-ls # doesn't use $PATH to lookup
bin desktop documents downloads examples.desktop music pictures ...
type
to see how an actual command will be resolved by the shell; e.g.: which echo
and type echo
will report different things, which
returns '/bin/echo' but 'type' returns that it's a shell builtin, which the shell will prefer over the file in '/bin'.
Nov 2, 2010 at 16:23
which
is better replaced by type
or command
in interactive shells, and it's completely useless in scripts.
$HOME
variable in $PATH
for some reason doesn't work, i.e. one have to use ~
sign instead.
Regarding ~/bin
or ~/.local/bin
and commands/programs only available to your user
Recent Ubuntu versions include the ~/bin
and ~/.local/bin
directories in your $PATH
, but only if either exist.
If none of these directory exists:
Ensure that your ~/.profile
contains the following stanza (the default ~/.profile
already does):
# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/bin" ] ; then
PATH="$HOME/bin:$PATH"
fi
# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/.local/bin" ] ; then
PATH="$HOME/.local/bin:$PATH"
fi
Create the ~/bin
and/or ~/.local/bin
directory:
mkdir -p ~/bin
and/or
mkdir -p ~/.local/bin
Either reboot your computer, or force bash to re-read ~/.profile
:
exec -l bash
exec -l bash
" tip. What does the -l
flag do? I'm not finding an explanation in man exec
.
Oct 19, 2013 at 6:11
exec -l
will execute bash as a login shell [wiki.bash-hackers.org/commands/builtin/exec]. In short, it force bash to re-read /etc/profile
and ~/.profile
. Just running exec bash
will only re-read ~/.bashrc
.
Oct 19, 2013 at 17:14