detect when there are no fds to pass.
* dcrt0.cc (host_dependent_constants::init): Revert Sat Mar 18 01:32:04 2000
change.
(dll_crt0_1): Set "cygwin_finished_initializing" flag.
(dll_crt0): Don't perform memcpy if uptr is already set to internal structure.
(_dll_crt0): Remember location of programs envptr.
* dll_init.h (per_module, dll, dll_list): Revamp.
* dll_init.cc: Revamp. Use new classes.
* fork.cc (fork): Use new revamped dll, dll_list, and per_module stuff.
* environ.cc: Use __cygwin_environ throughout rather than the
user_data->envptr.
* exec.cc: Ditto.
* spawn.cc: Ditto.
* winsup.h: Declare update_envptrs, cygwin_finished_initializing.
* lib/_cygwin_crt0_common.cc (_cygwin_crt0_common): Revert previous change.
* lib/cygwin_attach_dll.cc (cygwin_attach_dll): Always pass in own per_process
structure or we end up overwriting information from the main program.
name check. Windows 95 seems to null-terminate the directory otherwise.
(interrupt_on_return): Issue a fatal error if we can't find the caller's stack.
* spawn.cc (find_exec): Accept a path_conv argument rather than a buffer so
that the caller can find things out about a translated path.
(perhaps_suffix): Ditto.
(spawn_guts): Allocate path_conv stuff here so that we can find out stuff about
the translated path (this is work in progress).
* environ.cc (environ_init): Accept an as-yet unused argument indicating
whether we were invoked from a cygwin parent or not.
(winenv): Ditto.
(posify): Accept an argument indicating whether the path has already been
translated.
* dlfcn.cc (check_access): Provide a path_conv buffer to find_exec.
* exec.cc (sexecvpe): Ditto.
* path.cc (path_conv::check): Rename from path_conv::path_conv.
(mount_item::getmntent): Recognize "Cygwin executable" bit.
(symlink_info::check): Remove debugging statements.
* path.h (class path_conv): Add iscygexec method. Rewrite constructor to call
"check" method to allow multiple operations on a path_conv variable.
* pinfo.cc (pinfo_init): Pass argument to environ_init.
* shared.h: Bump PROC_MAGIC.
* winsup.h: Reflect above changes to function arguments.
* include/sys/mount.h: Add MOUNT_CYGWIN_EXEC type.
Christopher Faylor