MacOS – In Mountain Lion why do remote shells via ssh do NOT inherit the environment of the launchd parent process

command lineenvironment-variableslaunchdmacos

When logging in to my Mountain Lion Mac remotely via ssh I do not get the same PATH variable as when I open a shell locally: The local shell inherits its environment as expected from launchd and therefore has the PATH value I set in /etc/launchd.conf.

With the remote shell I hit a surprise: When I open a shell via ssh it does not inherit the environment variables set in /etc/launchd.conf although the related ssh processes all have launchd as their parents. Why???

A cut from a ps -ef output shows:

UID   PID  PPID   C STIME   TTY           TIME CMD
  0     1     0   0 Mon01PM ??         9:07.07 /sbin/launchd
.
.
.
501   150     1   0 Mon01PM ??         0:17.99 /sbin/launchd
.
.
.
501 39994   150   0 Thu11AM ??         0:00.72 /usr/bin/ssh-agent -l
.
.
.
  0 74002     1   0  2:08PM ??         0:00.05 /usr/sbin/sshd -i
501 74005 74002   0  2:08PM ??         0:00.00 /usr/sbin/sshd -i
501 74000  9844   0  2:08PM ttys000    0:00.02 ssh bridge@bridgethegap.local

I can fix the issue by setting PATH e.g. in .bashrc, but I'm in search for a way to give the same PATH to all applications launched under Mountain Lion (see In Mountain Lion how do I set the PATH environment variable…).

So my question is: Why do remote shells via ssh do not inherit the launchd environment?

Best Answer

I've looked for an answer too and eventually found a related answer to this question, How to set system-wide environment variables on OS X Mavericks.

It is a security measure, particularly to ensure secure shell users with a disabled shell, where SHELL is set to /bin/false, cannot gain unsolicited access.

One workaround is settting PermitUserEnvironment in your ssh config; please read security caveats in above mentioned answer before doing this.

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