> The wrong process is aborting when variable assignment fails
> in the vfork path. So the following command fails to execute
> the second echo (shown here with the correct output).
>
> $ (readonly r; r= /bin/echo a; echo b)
> r: is read only
> b
>
> fix: defer the mklocal() to the child shell.
> Also 'jobs' fails in a non-interactive shell.
> In showjobs(), the code that puts the process back into its
> own process group should only be run if the shell is actually
> doing job control - eg if 'mflag' is set.
$ /fred # non existant command
$ ^C # stops working
He says:
Ok the extra INTOFF is the one in exverror().
In almost all cases this doesn't matter because the longjmp()s
all end up in main() and the FORCEINTON call sorts it out
for the next command.
(There are a significant number of INTON/OFF mismatches through
the error paths...)
In any case the above failure can be 'fixed' by changing 2 (I think
they are both needed) INTON calls to FORCEINTON within evalcommand.
The following patch seems to work:
We should really look in the code and fix the INTON->INTOFF pairs.
effects, and add double to it, so that it aligns doubles correctly too. This
is just a workaround to fix the sparc64 problem where ALIGN() is now defined
in some include file to be 16 instead of 8. Thanks to martin for debugging this.
the non-vfork case. Having said that, it would be nice if pipelines of
simple commands were vforked too. Right now they are not.
Explain that setpgid() might fail because we are doing it both in the
parent and the child case, because we don't know which one will come
first.
Suspending a pipeline prints %1 Suspended n times where n is the number
of processes, but that was there before. It is easy to fix, but I'll
leave the code alone for now.
Propagate isroot, throughout the eval process and maintain it properly.
Fixes sleep 10 | cat^C not exiting because sleep and cat ended up in
their own process groups, because wasroot was always true in the children.
Plus my changes:
- walking process group fix in foregrounding a job.
- reset of process group in parent shell if interrupted before the wait.
- move INTON lower in the dowait so that the job structure is
consistent.
- error check all setpgid(), tcsetpgrp() calls.
- eliminate unneeded strpgid() call.
- check that we don't belong in the process group before we try to
set it.
race conditions -- now we always synchronously wait for the job to finish.
In evalcommand(), add the same INTOFF/INTON locking as evalpipe(), to prevent
leaving internal state inconsistent, and also to insure that we synchronously
wait for the job.
for TARGET_CHAR when building mksyntax. This isn't perfect, but
it lets the host tool work on non-BSD systems without completely
redoing how sh is built.
point to a tty.
Unfortunately the shell assumed that it could do all process group
handling ioctls to fd=2, but this is not correct. Jobs that redirected
fd=2 would be unable to perform the ioctls and silently fail since
the error reporting channel is fd=2... Instead open /dev/tty set
it to close on exec, and use that instead (like all other shells
do). We don't handle the case where the OS does not provide FD_CLOEXEC
or FIOCLEX, because I am lazy.
While I am there:
- Simplify the code by defining functions for tc{g,s}pgrp when OLD_TTY_DRIVER
is defined.
- make sure that 'sh &' works by stopping itself. Don't kill the shell's
process group, kill the shell itself.
commit where pipeline commands didn't inherit the correct process group.
Reviewed by Christos.
Change a trace format string arg to use %p instead of %x and a long cast.
the syntax maps to determine the beginning and end quotes (kill
CENDQUOTE). Handle single quotes opening and closing via checking
the current syntax map. Keep a bitmap of doublequote state one bit
per variable nesting level. For the first 32 nested double quotes,
we don't need any additional memory, but for more we allocate
dynamically.
