$PATH duplication issues

Question

If I do echo $PATH I get the following:

/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/usr/local/share/npm/bin:/usr/local/share/python:/opt/X11/bin:/Users/kh/.rvm/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/opt/X11/bin

This is in my ~/.zshrc file:

export PATH=/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/usr/local/share/npm/bin:/usr/local/share/python:/opt/X11/bin:$HOME/.rvm/bin:$PATH

I've had to manually add /usr/local/etc... at the front of this file because homebrew was complaining.

I've searched for all possibles files (I know of) to find where $PATH is being built from. But to no avail. These are

~/.bash_profile
~/.bashrc
~/.profile

Any suggestions.

Answer 1

Default paths are defined in /etc/paths on macOS. As a sub-process inherits environment variables and you explicitly set /usr/bin/ in your $PATH you have duplicate entries.

To remove the duplicate entries, you can use:

typeset -U PATH

The consequence of the above command is that only the first instance of any given directory path in the value of $PATH will be kept, while later duplicates are removed automatically. The effect is persistent in the current shell session, so adding new duplicates to the variable will be prevented.

Answer 2

I don't know which other file is setting your $PATH but the duplicated entries are

/opt/X11/bin
/usr/bin
/usr/local/bin
/usr/sbin

All of these are set in your ~/.zshrc so all you need to do is not set them there. In any case, these should all be in the default $PATH and there is no need to add them. Most systems come with a default $PATH that will include these directories, additions made in users' ~/.zshrc files should only add non-standard directories.

Change your $PATH declaration to

export PATH=/usr/local/sbin:/usr/local/share/npm/bin:/usr/local/share/python:$HOME/.rvm/bin:$PATH

Answer 3

According the the ZSH manual page:

STARTUP/SHUTDOWN FILES

Commands are first read from /etc/zshenv; this cannot be overridden. Subsequent behaviour is modified by the RCS and GLOBAL_RCS options; the former affects all startup files, while the second only affects global startup files (those shown here with an path starting with a /). If one of the options is unset at any point, any subsequent startup file(s) of the corresponding type will not be read. It is also possible for a file in $ZDOTDIR to re-enable GLOBAL_RCS. Both RCS and GLOBAL_RCS are set by default.

Commands are then read from $ZDOTDIR/.zshenv. If the shell is a login shell, commands are read from /etc/zprofile and then $ZDOTDIR/.zprofile. Then, if the shell is interactive, commands are read from /etc/zshrc and then $ZDOTDIR/.zshrc. Finally, if the shell is a login shell, /etc/zlogin and $ZDOTDIR/.zlogin are read.

Thus, you may want to check:

/etc/zshenv
/etc/zshrc
/etc/zlogin

and any files they happen to source. Since you are OS X, it is likely you'll find something like:

if [ -x /usr/libexec/path_helper ]; then
eval `/usr/libexec/path_helper -s`
fi

which, according to the path_helper man page, will also look in:

/etc/paths
/etc/paths.d/*

Answer 4

You can set additional paths to PATH using the following syntax:

PATH=$PATH:/additonally_location

So I think that PATH isn't duplicated.