It actually doesn't seem to be necessary: running 'otool -L' on the
real binary in the application bundle (Pterm-bin or PuTTY-bin) lists a
lot of paths starting with "@executable_path/../Resources/", which I
take to mean that the application is already set up to automatically
load the GTK shared libraries out of its own bundle directory, without
me having to give it the extra hint of DYLD_LIBRARY_PATH.
Moreover, I just got round to upgrading my Mac to High Sierra, and now
the version of osxlaunch _with_ DYLD_LIBRARY_PATH is causing a crash
at program load time, when the libpng in the MacOS system library
directory tries to use the libz in the application bundle and finds
that it doesn't provide an entry point it was expecting
('inflateValidate'). I could try to fix that by updating the libz
version in my OS X PuTTY build environment, but that seems to me to
set a precedent of running to keep up with any further dependencies
the system libraries happen to acquire in later releases. Better to
reset DYLD_LIBRARY_PATH so that the system libpng will load the system
libz and not get confused in the first place.
I've been having intermittent segfaults in this launcher program, and
by means of the new TEST_COMPILE_ON_LINUX facility introduced by
commit eef8cac28, I ran it under valgrind which helpfully pointed out
several pointers between linked-list nodes which I'd been relying on
OS memory allocation to happen to have zeroed for me.
By default, the program still builds on Linux to a stub that just
prints 'nothing to see here'. But if you compile with
-DTEST_COMPILE_ON_LINUX, it compiles to a program that still doesn't
do anything _actually_ useful, but goes through all the same motions
that real osxlaunch would go through, until the final execv(2) fails
because of course it's not _really_ living in an application bundle
directory of the right shape.
That allows me to run all the setup code under the debugging tools I'm
most used to, in my preferred environment. (Same rationale as having
puttyapp / ptermapp build for Linux too.)
[unix/osxlaunch.c:133] -> [unix/osxlaunch.c:134]: (warning) Either the condition '!qhead' is redundant or there is possible null pointer dereference: qhead.
The big problem with making an OS X application out of a GTK program
is that it won't start unless DYLD_LIBRARY_PATH and several other
environment variables point at all the GTK machinery. So your app
bundle has to contain two programs: a launcher to set up that
environment, and then the real main program that the launcher execs
once it's done so.
But in our case, we also need pterm to start subprocesses _without_
all that stuff in the environment - so our launcher has to be more
complicated than the usual one, because it's also got to save every
detail of how the environment was when it started up. So this is the
launcher program I'm going to use. Comments in the header explain in
more detail how it'll work.
Also in this commit, I add the other end of the same machinery to
gtkapp.c and uxpty.c: the former catches an extra command-line
argument that the launcher used to indicate how it had munged the
environment, and stores it in a global variable where the latter can
pick it up after fork() and use to actually undo the munging.
