On Windows, Mercurial can be run from the python script of from a frozen
executable. In the first case, we have to call the python interpreter since the
script is not executable. Frozen executable can be called directly.
Fix 3/3 for issue421
subprocess allows the environment and working directory to be specified
directly, so the hacks for making temporary changes while forking is no longer
necessary.
This also fixes failures on solaris where the temporary changes can't be undone
because there is no unsetenv.
The function is implemented for Mac OS X using the F_GETPATH fcntl,
and a basic implementation for Windows is provided as well. On other
POSIX systems, vanilla os.path.realpath() is used.
The fstat function was undefined, but never used since a stat object
was always passed in the optional st argument. Passing st is now
mandatory.
This bug crept in when util was split up into posix and windows
modules. The fstat function is still defined in util, but importing it
into posix would create an import cycle which seems unnecessary.
There is no standard python command to really detach a process under Windows.
Instead we use the low level API wrapped by subprocess module with all
necessary options to avoid any kind of context inheritance. Unfortunately, this
version still opens a new window for the child process.
The following have been tried:
- os.spawnv(os.P_NOWAIT): works but the child process is killed when parent
console terminates.
- os.spawnv(os.P_DETACH): works on python25, hang on python26 when writing to
the hgweb output socket.
- subprocess.CreateProcess() hack without shell mode: similar to
os.spawnv(os.P_DETACH).
Fix 1/3 for issue421
