hush/shell
Denys Vlasenko 4d12e944ea ash: [ERROR] Set exitstatus in onint
Partially backported this commit:

    Date: Thu, 2 Oct 2014 21:07:55 +0800
    [ERROR] Set exitstatus in onint

    Currently the exit status when we receive SIGINT is set in evalcommand
    which means that it doesn't always get set.  For example, if you press
    CTRL-C at the prompt of an interactive dash, the exit status is not
    set to 130 as it is in many other Bourne shells.

    This patch fixes this by moving the setting of the exit status into
    onint which also simplifies evalcommand.

    Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The part after "if (evalbltin(cmdentry.u.cmd, argc, argv, flags))"
causes testsuite failures in signal handling, so left unchanged.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-10-01 16:03:11 +02:00
..
ash_test shell testsuite: add trailing newline to var_unbackslash1.tests 2016-09-29 20:02:53 +02:00
hush_test shell testsuite: add trailing newline to var_unbackslash1.tests 2016-09-29 20:02:53 +02:00
msh_test whitespace fixes 2010-01-25 13:39:24 +01:00
ash_doc.txt
ash_ptr_hack.c *: make GNU licensing statement forms more regular 2010-08-16 20:14:46 +02:00
ash.c ash: [ERROR] Set exitstatus in onint 2016-10-01 16:03:11 +02:00
brace.txt hush: wait for cmd to complete, and immediately store its exitcode in $? 2009-11-15 19:58:19 +01:00
Config.src config: disentangle PREFER_APPLETS from SH_STANDALONE and SH_NOFORK 2016-07-22 18:48:38 +02:00
cttyhack.c cttyhack: handle multiple consoles found in sysfs 2012-02-04 21:55:01 +01:00
hush_doc.txt
hush_leaktool.sh
hush.c hush: enable "msh is deprecated" message in msh stub 2016-09-30 12:28:37 +02:00
Kbuild.src *: make GNU licensing statement forms more regular 2010-08-16 20:14:46 +02:00
match.c shell/match.c: shrink by dropping double bool inversion 2010-09-12 15:06:42 +02:00
match.h hush: optimize #[#] and %[%] for speed. size -2 bytes. 2010-09-04 21:21:07 +02:00
math.c typo fix in comment 2014-11-20 01:43:30 +01:00
math.h move endofname() to libbb 2013-02-26 00:36:53 +01:00
random.c ash,hush: fix a thinko about 2^64-1 factorization 2014-03-15 09:25:46 +01:00
random.h ash,hush: improve randomness of $RANDOM, add easy-ish way to test it 2014-03-13 12:52:43 +01:00
README update shell/README 2010-05-20 12:56:14 +02:00
README.job
shell_common.c ash: [VAR] Initialise OPTIND after importing environment 2016-09-30 14:46:41 +02:00
shell_common.h ash: [VAR] Initialise OPTIND after importing environment 2016-09-30 14:46:41 +02:00

http://www.opengroup.org/onlinepubs/9699919799/
Open Group Base Specifications Issue 7


http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap01.html
Shell & Utilities

It says that any of the standard utilities may be implemented
as a regular shell built-in. It gives a list of utilities which
are usually implemented that way (and some of them can only
be implemented as built-ins, like "alias"):

alias
bg
cd
command
false
fc
fg
getopts
jobs
kill
newgrp
pwd
read
true
umask
unalias
wait


http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html
Shell Command Language

It says that shell must implement special built-ins. Special built-ins
differ from regular ones by the fact that variable assignments
done on special builtin are *PRESERVED*. That is,

VAR=VAL special_builtin; echo $VAR

should print VAL.

(Another distinction is that an error in special built-in should
abort the shell, but this is not such a critical difference,
and moreover, at least bash's "set" does not follow this rule,
which is even codified in autoconf configure logic now...)

List of special builtins:

. file
: [argument...]
break [n]
continue [n]
eval [argument...]
exec [command [argument...]]
exit [n]
export name[=word]...
export -p
readonly name[=word]...
readonly -p
return [n]
set [-abCefhmnuvx] [-o option] [argument...]
set [+abCefhmnuvx] [+o option] [argument...]
set -- [argument...]
set -o
set +o
shift [n]
times
trap n [condition...]
trap [action condition...]
unset [-fv] name...

In practice, no one uses this obscure feature - none of these builtins
gives any special reasons to play such dirty tricks.

However. This section also says that *function invocation* should act
similar to special built-in. That is, variable assignments
done on function invocation should be preserved after function invocation.

This is significant: it is not unthinkable to want to run a function
with some variables set to special values. But because of the above,
it does not work: variable will "leak" out of the function.