Re: PATH reordered when running zsh inside screen on Mac OS X Mountain Lion and MacPorts

[Lawrence Velázquez <larryv@xxxxxxxxxxxx>]

On Jan 28, 2013, at 5:08 AM, Nikolai Weibull <now@xxxxxxxx> wrote:

> I figured out what the problem was.  /etc/zshenv on Mac OS X Mountain Lion calls a utility called path_helper.

The /usr/libexec/path_helper program is used by prior versions of OS X also, albeit implemented differently. (At one point it was a shell script.) Its purpose is to create a default ${PATH} and ${MANPATH} using the contents of /etc/{paths,manpaths} and /etc/{paths,manpaths}.d.

For more details, see the path_helper(8) man page[1]. For way too many details, see the path_helper source code[2].

    [1] https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man8/path_helper.8.html.
    [2] http://www.opensource.apple.com/source/shell_cmds/shell_cmds-170/path_helper/path_helper.c

> Oh, and why /etc/zshenv in Mac OS X Mountain Lion modifies path in this way is way beyond me.  In my world, that’d go into /etc/zprofile.

I agree that /etc/zprofile would be a better place to set ${PATH}, but you would still run into the issue because terminal multiplexers usually run login shells. I previously encountered it under tmux.

The real problem is that /usr/libexec/path_helper alters ${PATH} even if ${PATH} already contains the entries it wants to add. In this case, it moves the entries to the beginning of ${PATH} instead of just leaving it as is.

> as far as I can tell, this didn’t occur before I upgraded to 5.0.2 (from zsh-devel? (which was at 5.0.0?), can’t remember).

The old zsh-devel port did use --enable-etcdir in its configure phase. For the reason given by Phil, I chose not to carry this over to the zsh port when I assumed maintenance of both and obsoleted zsh-devel.

vq