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Diffstat (limited to 'winsup/cygwin/how-spawn-works.txt')
| -rw-r--r-- | winsup/cygwin/how-spawn-works.txt | 33 |
1 files changed, 0 insertions, 33 deletions
diff --git a/winsup/cygwin/how-spawn-works.txt b/winsup/cygwin/how-spawn-works.txt deleted file mode 100644 index e865ebf3e..000000000 --- a/winsup/cygwin/how-spawn-works.txt +++ /dev/null @@ -1,33 +0,0 @@ -(THIS DESCRIPTION IS OUT-OF-DATE) -Spawn.cc in cygwin handles spawn, vfork and exec calls. It does this via -a mode parameter that determines its behaviour with respect to the -child. - -Of particular interest is the exec behaviour. - -In general spawn_guts (where the action happens) does the following: -* Finds the actual program being run (which may include path searching). -* Determines the type (.exe, shell script, perl etc) and for non binary -programs finds the correct interpreter. -* Creates a commandline (based on the type and the user parameters). -* Guesses at whether the binary that will be invoked is a cygwin program -or not (if (real_path.iscygexec ())) and uses that information to copy -the argv table, or to translate it for win32 program usage. -* passes a handle to the parent to the child (note: this handle should -have it's rights restricted the daemon is merged). -* Start the process. -* if the mode is _P_OVERLAY (we are doing an exec) -wait for the child to -a) if it's a cygwin process, signal us via an event. -b) if it's a win32 process, exit. -c) exit. - -If a) occurs, we 'reparent' the child which makes it look to the current -process's parent in the pid and process group chains. -b) is where the cygwin process hangs around as a 'stub' presenting it's -pid as the win32 process's pid, to allow cygwin tools to kill the win32 -process. -once a-c has occured, execution resumes. -* If the mode is _P_OVERLAY, this process exits, otherwise it's -behaviour depends on the mode parameter. See the last block of -spawn_guts. |