CVS commit: src/bin/sh

["Robert Elz" <kre%netbsd.org@localhost>]

Module Name:    src
Committed By:   kre
Date:           Fri Feb  3 23:16:38 UTC 2017

Modified Files:
        src/bin/sh: redir.c

Log Message:
Fiddle the (new) fdflags implementation:

Remove some unnecessary cuteness that limited error reporting.
Permit just one -s arg to fdflags
Be deterministic in the case of fdflags -s +cloexec,-cloexec 0
        (and similar) - use the last specified, always.
Allow:
        FD_0_FLAGS=$( fdflags -v 0 )
        # do stuff, manipulating the flags
        fdflags -s "FD_0_FLAGS" 0
to save/restore flags for a fd.
Correctly mask result of fcntl(fd, F_GETFD) with FD_CLOEXEC as the
specs require before deciding close on exec is set.

Improve portability as a tool, don't assume strtoi(), nor __arraycount()
and avoid needlessly requiring recent C versions (ie: there's no need to
sprinkle declarations in the middle of the code, it just makes them hard
to find, and benefits nothing.)

Still to do:  As currently implemented, both user, and shell internal fds
are reported, and can be manipulated.  Allowing users to touch the shell's
internal fds is bogus, and providing this easy way to allow users to
discover which values they have is poor.   Fixing this means getting rid
of the use of fcntl(F_MAXFD) and replacing it with a shell maintained
memory of what fds the user (script) has allocated.   The shell's fd
manipulation really still needs major work (including properly fixing
bin/48875)


To generate a diff of this commit:
cvs rdiff -u -r1.50 -r1.51 src/bin/sh/redir.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.