'typeset -xu' and 'typeset -xl' would export the variable but fail
to change case in the value under certain conditions.
Original patch:
642af4d6/f/ksh-20120801-xufix.patch
This applies the patch essentially without change and adds a
regression test based on the reproducer provided in the RH bug.
Unfortunately there is no description of how the patch works and
it's a little obscure to me. As far as I can figure out, the cause
of the problem was that nv_newattr() erroneously processed a
nonexistent size option-argument such as what can be given to
options like typeset -F, e.g. typeset -F3 for 3 digits after the
dot. A nonexistent size argument is represented by the value of -1.
The undocumented alarm builtin executes actions unsafely so that
'read' with an IFS assignment crashed when an alarm was triggered.
This applies an edited version of a Red Hat patch:
642af4d6/f/ksh-20120801-alarmifs.patch
Prior discussion:
https://bugzilla.redhat.com/1176670
src/cmd/ksh93/bltins/alarm.c:
- Add a TODO note based on dgk's 2014 email cited in the RH bug.
- When executing the trap function, save and restore the IFS table.
src/cmd/ksh93/sh/init.c: get_ifs():
- Remove now-unnecessary SHOPT_MULTIBYTE preprocessor directives as
8477d2ce lets the compiler optimise out multibyte code if needed.
- Initialise the 0 position of the IFS table to S_EOF. This
corresponds with the static state tables in data/lexstates.c.
src/cmd/ksh93/tests/builtins.sh:
- Crash test.
According to 'whence --man', 'whence -f' should ignore functions:
-f Do not check for functions.
Right now this is only accomplished partially. As of commit
a329c22d 'whence -f' avoids any output when encountering a
function (in ksh93u+ 'whence -f' has incorrect output). The
return value is still wrong though:
$ foo() { true; }
$ whence -f foo; echo $?
0
This commit fixes the return value and makes 'type -f' error out
when given a function (like in Bash).
src/cmd/ksh93/bltins/whence.c:
- If -f was passed, set 'cp' to NULL since functions should be
ignored (as documented).
- Simplify return value by avoiding bitwise logic.
src/cmd/ksh93/tests/builtins.sh:
- Add regression tests for 'whence -f' and 'type -f'.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
Since at least 1999, whence -v on pdksh (and its successor mksh)
reports the path where an autoloadable function may be found:
$ mkdir ~/fun; FPATH=~/fun
$ echo 'myfn() { echo hi; }' >~/fun/myfn
$ whence -v myfn
myfn is a undefined (autoload from /home/user/fun/myfn) function
Whereas ksh93 only reports, rather uselessly:
myfn is an undefined function
As of this commit, whence -v/-a on ksh 93u+m does the same as
pdksh, but with correct grammar:
myfn is an undefined function (autoload from /home/user/fun/myfn)
This may be a small violation of my own "no new features" policy
for 93u+m, but I couldn't resist. This omission has been annoying
me, and it's just embarrassing to lack a pdksh feature :)
src/cmd/ksh93/include/path.h,
src/cmd/ksh93/data/msg.c:
- Add e_autoloadfrom[] = " (autoload from %s)" message.
src/cmd/ksh93/bltins/whence.c: whence():
- Report the path (if any) when reporting an undefined function.
This needs to be done in two places:
1. When a function has been explicitly marked undefined with
'autoload', we need to do a quick path_search() loop to find
the path. (These undefined functions take precedence over
regular commands, so are reported first.)
2. When a function is not explicitly autoloaded but merely
available in $FPATH, that path search was already done, so all
we need to do is report it. (These are reported last.)
Note that the output remains as on 93u+ if no function definition
file is found on $FPATH. This is also like pdksh/mksh.
src/cmd/ksh93/data/builtins.c:
- Bump 'whence' version date. The inline docs never detailed very
exactly what 'whence -v' reports, so no need for further edits.
src/cmd/ksh93/tests/path.sh:
- Regress-test the new whence behaviour plus actual autoloading,
including the command override behaviour of autoloaded functions.
Hopefully this doesn't introduce new bugs, but it does fix at
least the following:
1. When whence -v/-a found an "undefined" (i.e. autoloadable)
function in $FPATH, it actually loaded the function as a side
effect of reporting on its existence (!). Now it only reports.
2. 'whence' will now canonicalise paths properly. Examples:
$ whence ///usr/lib/../bin//./env
/usr/bin/env
$ (cd /; whence -v dev/../usr/bin//./env)
dev/../usr/bin//./env is /usr/bin/env
3. 'whence' no longer prefixes a spurious double slash when doing
something like 'cd / && whence bin/echo'. On Cygwin, an initial
double slash denotes a network server, so this was not just a
cosmetic problem.
4. 'whence -a' now reports a "tracked alias" (a.k.a. hash table
entry, i.e. cached $PATH search) even if an actual alias by the
same name exists. This needed fixing because in fact the hash
table entry continues to be used when bypassing the alias.
Aliases and "tracked aliases" are not remotely the same thing;
confusing nomenclature is not a reason to report wrong results.
5. When using 'hash' or 'alias -t' on a command that is also a
builtin to force caching a $PATH search for the external
command, 'whence -a' double-reported the path:
$ hash printf; whence -a printf
printf is a shell builtin
printf is /usr/bin/printf
printf is a tracked alias for /usr/bin/printf
This is now fixed so that the second output line is gone.
Plus, if there were multiple versions of the command on $PATH,
the tracked alias was reported at the end, which is the wrong
order. This is also fixed.
src/cmd/ksh93/bltins/whence.c: whence():
- Refactor the do...while loop that handles whence -v/-a for path
searches in such a way that the code actually makes sense and
stops looking like higher esotericism. Just doing this fixed#2,
#4 and #5 above (the latter two before I even noticed them). For
instance, the path_fullname() call to canonicalise paths was
already there; it was just never used.
- Remove broken 'notrack' flaggery for deciding whether to report a
hash table entry a.k.a. "tracked alias"; instead, check the hash
table (shp->track_tree).
src/cmd/ksh93/sh/path.c:
- path_search(): Re #3: When prefixing the PWD, first check if
we're in '/' and if so, don't prefix it; otherwise, adding the
next slash causes an initial double slash. (Since '/' is the only
valid single-character absolute path, all we need to do is check
if the second character pwd[1] is non-null.)
- path_search(): Re #1: Stop autoloading when called by 'whence':
* The 'flag==2' check to avoid autoloading a function was
broken. The flag value is 2 on the first whence() loop
iteration, but 3 on subsequent ones. Change to 'flag >= 2'.
* However, this only fixes it if the function file does not have
the x permission bit, as executable files are handled by
path_absolute() which unconditionally autoloads functions!
So, pass on our flag parameter when callling path_absolute().
- path_absolute(): Re #1: Add flag parameter. Do not autoload
functions if flag >= 2.
src/cmd/ksh93/include/path.h,
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/sh/main.c,
src/cmd/ksh93/sh/xec.c:
- Re #1: Update path_absolute() calls, adding a 0 flag parameter.
src/cmd/ksh93/include/name.h:
- Remove now-unused pathcomp member from union Value. It was
introduced in 99065353 to allow examining the value of a tracked
alias. This commit uses nv_getval() instead.
src/cmd/ksh93/tests/builtins.sh,
src/cmd/ksh93/tests/path.sh:
- Add and tweak various related tests.
Fixes: https://github.com/ksh93/ksh/issues/84
The following set of commands caused ksh to crash:
$ unalias history; unalias r
Memory fault
When ksh is compiled with -D_std_malloc, the crash always
occurs when the 'r' alias is removed with 'unalias r',
although with vmalloc 'unalias history' must be run first
for the crash to occur. With the native malloc, the crash
message is also different:
$ unalias history; unalias r
free(): invalid pointer
Abort
This crash happens because when an alias is unset, _nv_unset
removes the NV_NOFREE flag which results in an invalid use
of free(3) as nv_isattr no longer detects NV_NOFREE afterward.
The history and r aliases shouldn't be freed from memory by
nv_delete because those aliases are given the NV_NOFREE attribute.
src/cmd/ksh93/bltins/typeset.c:
- Save the state of NV_NOFREE for aliases to fix the crash
caused by 'unalias r'.
src/cmd/ksh93/tests/alias.sh:
- Use unalias on both history and r to check for the crash.
'unalias -a' can't be used to replicate the crash.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
Following a community discussion, it became clear that 'r' is
particularly problematic as a regular builtin, as the name can and
does conflict with at least one legit external command by that
name. There was a consensus against removing it altogether and
letting users set the alias in their login scripts. However,
aliases are easier to bypass, remove or rename than builtins are.
My compromise is to reinstate 'r' as a preset alias on interactive
shells only, along with 'history', as was done in 17f81ebe before
they were converted to builtins in 03224ae3. So this reintroduces
the notion of predefined aliases to ksh 93u+m, but only for
interactive shells that are not initialised in POSIX mode.
src/cmd/ksh93/Makefile,
src/cmd/ksh93/Mamfile,
src/cmd/ksh93/include/shtable.h,
src/cmd/ksh93/data/aliases.c:
- Restore aliases.c containing shtab_aliases[], a table specifying
the preset aliases.
src/cmd/ksh93/include/shtable.h,
src/cmd/ksh93/sh/init.c:
- Rename inittree() to sh_inittree() and make it extern, because we
need to use it in main.c (sh_main()).
src/cmd/ksh93/sh/main.c: sh_main():
- Init preset aliases from shtab_aliases[] only if the shell is
interactive and not in POSIX mode.
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/tests/alias.sh:
- unall(): When unsetting an alias, pass on the NV_NOFREE attribute
to nv_delete() to avoid an erroneous attempt to free a preset
alias from read-only memory. See: 5d50f825
src/cmd/ksh93/data/builtins.c:
- Remove "history" and "r" entries from shtab_builtins[].
- Revert changes to inline fc/hist docs in sh_opthist[].
src/cmd/ksh93/bltins/hist.c: b_hist():
- Remove handling for 'history' and 'r' as builtins.
src/cmd/ksh93/sh.1:
- Update accordingly.
Resolves: https://github.com/ksh93/ksh/issues/125
The 'exit' and 'return' commands without an argument failed to pass
down the exit status of the last-run command when incorporated in a
block with redirection, &&/|| list, 'case' statement, or 'while',
'until' or 'for' loop.
src/cmd/ksh93/bltins/cflow.c:
- Use $?, which is sh.savexit a.k.a. shp->savexit, as the default
exit status value if there is no argument, instead of
shp->oldexit. This fixes the default exit status behaviour to
match POSIX and other shells.
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/include/shell.h:
- Remove now-unused sh.oldexit (a.k.a. shp->oldexit) private struct
member. It appeared to fulfill the same function as sh.savexit,
but in a slightly broken way.
- Move the savexit/$? declaration from the _SH_PRIVATE part of the
struct definition to the public API part. Since $? uses this,
it's clearly a publicly exposed value already, and this is
generally the one to use. (If anything, it's exitval that should
have been private.) This declares savexit right next to exitval,
rewriting the comments to clarify the difference between them.
src/cmd/ksh93/sh/fault.c,
src/cmd/ksh93/sh/subshell.c,
src/cmd/ksh93/sh/xec.c:
- Remove assignments to shp->oldexit.
src/cmd/ksh93/tests/basic.sh:
- Add thorough regression tests for the default exit status
behaviour of 'return' and 'exit' in various lexical contexts.
- Verify that 'for' and 'case' without any command, as well as a
lone redirection, still correctly reset the exit status to 0.
Fixes: #117
Using a process of elimination I've identified ${.sh.level}
(SH_LEVELNOD) as the cause of the crash. This node apparently
cannot be copied or moved without destabilising the shell. It
contains the current depth of function calls and it cannot be
changed by assignment, so this is not actually a problem.
Meanwhile, this commit re-fixes it for the other three.
src/cmd/ksh93/sh/subshell.c:
- Simplify sh_assignok() by removing special-casing for L_ARGNOD,
SH_SUBSCRNOD and SH_NAMENOD. 'add' now has 3 modes (0, 1, 2).
- The test for a ${ subshare; } was actually wrong. sp->subshare is
a saved backup value. We must test shp->subshare. (re: a9de50bf)
src/cmd/ksh93/bltins/typeset.c:
- setall(): Update the mode 3 sh_assignok() call.
src/cmd/ksh93/tests/variables.sh:
- Regress-test subshell leaks for all special variables except
${.sh.level}.
This reverts commit b3d37b00b0.
While ksh's own regression test suite passed just fine, when
running the modernish[*] regression tests uite, ksh either froze
hard (needing SIGKILL) or threw a spurious syntax error.
Cause unknown, but I'm certainly reverting until I find out.
This reintroduces a subshell leak for four special variables.
[*] https://github.com/modernish/modernish
The following special variables leaked out of a subshell:
$_, ${.sh.name}, ${.sh.level}, ${.sh.subscript}.
This was due to a faulty optimisation in sh_assignok().
bd3e2a80 fixed that in part, this fixes the rest.
src/cmd/ksh93/sh/subshell.c:
- Simplify sh_assignok() by removing special-casing for these four
special variables. The 'add' param reverts to a simple boolean.
- The test for a ${ subshare; } was actually wrong. sp->subshare is
a saved backup value. We must test shp->subshare. (re: a9de50bf)
src/cmd/ksh93/bltins/typeset.c:
- setall(), unall(): Update sh_assignok() calls.
src/cmd/ksh93/tests/variables.sh:
- Regress-test subshell leaks for all special variables.
Closes: #122
Since ksh 93u+m comes bundled with libast 20111111, there's no need
to support older versions, so this is another cleanup opportunity.
src/cmd/ksh93/include/defs.h:
- Throw an #error if AST_VERSION is undefined or < 20111111.
(Note that _AST_VERSION is the same as AST_VERSION, but the
latter is newer and preferred; see src/lib/libast/features/api)
All other changed files:
- Remove legacy code for versions older than the currently used
versions, which are:
_AST_VERSION 20111111
ERROR_VERSION 20100309
GLOB_VERSION 20060717
OPT_VERSION 20070319
SFIO_VERSION 20090915
VMALLOC_VERSION 20110808
SHOPT_ENV is an undocumented compile-time option implementing an
experimental method for handling environment variables, which is
implemented in env.h and env.c. There is no mention in the docs or
Makefile, and no mention in the mailing list archives. It adds no
new functionality, but at first glance it's a clean-looking
interface.
However, unfortunately, it's broken. Compiling with -DSHOPT_ENV
added to CCFLAGS causes bin/shtests to show these regressions:
functions.sh[341]: export not restored name=value function call -- expected 'base', got ''
functions.sh[1274]: Environment variable is not passed to a function
substring.sh[236]: export not restored name=value function call
variables.sh[782]: SHLVL should be 3 not 2
In addition, 'export' stops working on unset variables.
In the 93v- beta this code is still present, unchanged, though 93v-
made lots of incompatible changes. By the time ksh2020 noticed it,
it was no longer compiling, so it probably wasn't compiling in the
93v- beta either. Discussion: https://github.com/att/ast/issues/504
So the experiment was already abandoned by D. Korn and his team.
Meanwhile it was leaving sh/name.c with two versions of several
enviornment-related functions, and it's not clear which one is
actually compiled without doing detective work tracing header files
(most of the code was made conditional on _ENV_H, which is defined
in env.h, which is included by defs.h if SHOPT_ENV is defined).
This actively hinders understanding of the codebase. And any
changes to these functions would need to be implemented twice.
src/cmd/ksh93/include/env.h,
src/cmd/ksh93/sh/env.c:
- Removed.
src/cmd/ksh93/DESIGN,
src/cmd/ksh93/Makefile,
src/cmd/ksh93/Mamfile:
- Update accordingly.
All other changed files:
- Remove deactivated code behind SHOPT_ENV and _ENV_H.
On ksh93, 'test -t' is equivalent to 'test -t 1' (and of course
"[ -t ]" is equivalent to "[ -t 1 ]").
This is purely for compatibility with ancient Bourne shell
breakage. No other shell supports this. ksh93 should probably keep
it for backwards compatibility, but it should definitely be
disabled in POSIX mode as it is a violation of the standard; 'test
-t' is an instance of 'test "$string"', which tests if the string
is empty, so it should test if the string '-t' is empty (quod non).
This also replaces the fix for 'test -t 1' in a command
substitution with a better one that avoids forking (re: cafe33f0).
src/cmd/ksh93/sh/parse.c:
- qscan(): If the posix option is active, disable the parser-based
hack that converts a simple "[ -t ]" to "[ -t 1 ]".
src/cmd/ksh93/bltins/test.c:
- e3(): If the posix option is active, disable the part of the
compatibility hack that was used for compound expressions
that end in '-t', e.g. "[ -t 2 -o -t ]".
- test_unop(): Remove the forking fix for "[ -t 1 ]".
src/cmd/ksh93/edit/edit.c:
- tty_check(): This function is used by "[ -t 1 ]" and in other
contexts as well, so a fix here is more comprehensive. Forking
here would cause a segfault, but we don't actually need to. This
adds a fix that simply returns false if we're in a virtual
subshell that is also a command substitution. Since command
substitutions always fork upon redirecting standard output within
them (making them no longer virtual), it is safe to do this.
src/cmd/ksh93/tests/bracket.sh
- Add comprehensive regression tests for test/[/[[ -t variants in
command substitutions, in simple and compound expressions, with
and without redirecting stdout to /dev/tty within the comsub.
- Add tests verifying that -o posix disables the old hack.
- Tweak other tests, including one that globally disabled xtrace.
Following a community objection to its removal, the inline 'test'
manual page along with its strange method of invocation is
restored. I've taken the opportunity to correct several mistakes,
add some missing info, do some copy-editing, and document the way
to get these docs in the main (k)sh.1 manual.
Discussion:
fa6a180f (commitcomment-41897553)
Did you know that you could get a manual page for the 'test'/'['
builtin command using one of these strange command lines?
test --man --
[ --man -- ]
Neither did I. It's not documented or mentioned anywhere (and this
syntax violates POSIX). So nobody knows about it, which makes that
documentation useless. (The regular --man option doesn't work
because that would break 'test'.) I only found out how to invoke it
when I understood what the uncommented C code handling this does.
The test/[ command's self-documentation is unmaintained since 2003
and somewhat incomplete. It's also mostly redundant with the
documentation on Conditional Expressions in the main (k)sh.1 manual
page. But unlike the latter, this is resident in RAM, wasting
working memory in every shell process.
src/cmd/ksh93/sh.1:
- Add documentation for 'test'/'[' commands (yes, they were not
mentioned in the main manual page until now), describing them
in terms of differences from '[[' and recommending the latter.
src/cmd/ksh93/include/test.h,
src/cmd/ksh93/bltins/test.c,
src/cmd/ksh93/data/testops.c:
- Remove RAM-resident --man doc for test/[ command.
- Remove the bizarre option parsing that allowed invoking it.
Instead of a global 'sh_in_test_builtin' integer flag, it is nicer
to use the mechanism for shell state bits, which was designed for
this sort of thing.
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/sh/defs.c:
- Remove global sh_in_test_builtin integer.
- Define new SH_INTESTCMD state bit.
src/cmd/ksh93/bltins/test.c: _ERROR_exit_b_test(), b_test():
- Use the new state bit.
This removes various blocks of uncommented experimental code that
was disabled using '#if 0' or '#if 1 ... #else' directives. It's
hard or impossible to figure out what the thoughts behind them
might have been, and we can really do without those distractions.
As of 8477d2ce, the mbwide() macro (which tests if we're in a
multibyte locale, i.e. UTF-8) is redefined as a constant 0 if we're
compiling without SHOPT_MULTIBYTE. See src/cmd/ksh93/include/defs.h
The other multibyte macros use mbwide() as well, so they all revert
to the single-byte fallbacks in that case, and the multibyte code
in them is never compiled. See src/lib/libast/include/ast.h
Consequently we can now do a bit of cleanup and get rid of many of
the '#if SHOPT_MULTIBYTE' directives, as the compiler optimiser
will happily remove the multibyte-specific code. This increases the
legibility of the ksh code.
I'm taking the opportunity to fix a few typos and whitespace
formatting glitches as well.
A memory leak occurred upon leaving a virtual subshell if a
function was defined within it. If this was done more than 32766
(= 2^15-2 = the 'short' max value - 1) times, the shell crashed.
Discussion and reproducer: https://github.com/ksh93/ksh/issues/114
src/cmd/ksh93/sh/subshell.c: table_unset():
- A subshell-defined function was never freed because a broken
check for autoloaded functions (which must not be freed[*]). It
looked for an initial '/' in the canonical path of the script
file that defined the function, but that path is also stored for
regular functions. Now use a check that executes nv_search() in
fpathdict, the same method used in _nv_unset() in name.c for a
regular function unset.
src/cmd/ksh93/bltins/misc.c: b_dot_cmd():
- Fix an additional memory leak introduced in bd88cc7f, that caused
POSIX functions (which are run with b_dot_cmd() like dot scripts)
to leak extra. This fix avoids both the crash fixed there and the
memory leak by introducing a 'tofree' variable remembering the
filename to free. Thanks to Johnothan King for the patch.
src/lib/libast/include/stk.h,
src/lib/libast/misc/stk.c,
src/lib/libast/man/stk.3,
src/lib/libast/man/stak.3:
- Make the stack more resilient by extending the stack reference
counter 'stkref' from (signed) short to unsigned int. On modern
systems with 32-bit ints, this extends the maximum number of
elements on a stack from 2^15-1==32767 to 2^32-1==4294967295.
The ref counter can never be negative, so there is no reason for
signedness. sizeof(int) is defined as the size of a single CPU
word, so this should not affect performance at all.
On a 16-bit system (not that ksh still compiles there), this
doubles the max number of entries to 2^16-1=65535.
src/cmd/ksh93/tests/leaks.sh:
- Add leak regression tests for ksh functions, POSIX functions, dot
scripts run with '.', and dot scripts run with 'source'.
src/cmd/ksh93/tests/path.sh:
- Add an output builtin with a redirect to an autoloaded function
so that a crash[*] is triggered if the check for an autoloaded
function is ever removed from table_unset(), as was done in ksh
93v- (which crashed).
[*] Freeing autoloaded functions after leaving a virtual subshell
causes a crashing bug: https://github.com/att/ast/issues/803
Co-authored-by: Johnothan King <johnothanking@protonmail.com>
Fixes: https://github.com/ksh93/ksh/issues/114
src/cmd/ksh93/bltins/print.c:
- If in UTF-8 locale, only bother to check for unreserved char if
the character is ASCII (< 128), and write unreserved chars with
a simple stakputc().
The entity is not valid in XML, only in HTML. Since we must
be compatible with both, it can't be used. Thanks to Andras Farkas
for the bug report.
In addition, the generation of numeric entities for unprintable
characters was only valid while processing UTF-8 text while in a
UTF-8 locale. In all other conditions it produced invalid results.
This is not worth trying to fix.
Discussion:
https://groups.google.com/d/msgid/korn-shell/CAA0nTRta%3DPbOYduyBv%3DXCzumTcUCU8Lki%3DQQf2O8Erk2BFvO1g%40mail.gmail.com
src/cmd/ksh93/bltins/print.c:
- Remove conversion to entity.
- Remove conversion of non-graph characters to numeric entities.
Convert only the 5 semantically meaningful characters: < > & " '
src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/sh/string.c:
- We don't need sh_isprint() in print.c anymore, so turn it back
into a static function.
src/cmd/ksh93/tests/builtins.sh:
- Update and trim regression tests.
This applies a number of fixes to the printf formatting directives
%H and %#H (as well as their equivalents %(html)q and %(url)q):
1. Both formatters have been made multibyte/UTF-8 aware, and no
longer delete multibyte characters. Invalid UTF-8 byte sequences
are rendered as ASCII question marks.
2. %H no longer wrongly encodes spaces as non-breaking spaces
( ) and instead correctly encodes the UTF-8 non-breaking
space as such.
3. %H now converts the single quote (') to '%#39;' instead of
''' which is not a valid entity in all HTML versions.
4. %#H failed to encode some reserved characters (e.g. '?') while
encoding some unreserved ones (e.g. '~'). It now percent-encodes
all characters except those 'unreserved' as per RFC3986 (ASCII
alphanumeric plus -._~).
Prior discussion:
ce8d1467-4a6d-883b-45ad-fc3c7b90e681%40inlv.org
src/cmd/ksh93/include/defs.h:
src/cmd/ksh93/sh/string.c:
- defs.h: If compiling without SHOPT_MULTIBYTE, redefine the
mbwide() macro (which tests if we're in a multibyte locale) as 0.
This lets the compiler optimiser do the work that would otherwise
require a lot of tedious '#if SHOPT_MULTIBYTE' directives.
- string.c: Remove some now-unneeded '#if SHOPT_MULTIBYTE' stuff.
- defs.h, string.c: Rename is_invisible() to sh_isprint(), invert
the boolean return value, and make it an extern for use in
fmthtml() -- see below. If compiling without SHOPT_MULTIBYTE,
simply #define sh_isprint() as equivalent to isprint(3).
- defs.h: Add URI_RFC3986_UNRESERVED macro for fmthtml() containing
the characters "unreserved" for purposes of URI percent-encoding.
src/cmd/ksh93/bltins/print.c: fmthtml():
- Remove kludge that skipped all multibyte characters (!).
- Complete rewrite to implement fixes described above.
- Don't bother with '#if SHOPT_MULTIBYTE' directives (see above).
src/cmd/ksh93/data/builtins.c:
- sh_optprintf[]: %H: Add single quote to encoded chars doc.
- Edit credits and bump version date.
src/cmd/ksh93/tests/builtins.sh:
- Update and tweak old regression tests.
- Add a number of new tests for UTF-8 HTML and URI encoding, which
are only run when running tests in a UTF-8 locale (shtests -u).
The 'redirect' builtin command did not error out before executing
any valid redirections. For example, 'redirect ls >foo.txt' issued
an "incorrect syntax" error, but still created 'foo.txt' and left
standard output permanently redirected to it.
src/cmd/ksh93/sh/xec.c: sh_exec():
- If we have redirections (io != NULL), and the command is
SYSREDIR, then check for arguments and error out if there are
any, before calling sh_redirect() to execute redirections.
(Note, the other check for arguments in b_exec() in bltins/misc.c
must be kept, as that applies if there are no redirections.)
src/cmd/ksh93/sh/io.c: sh_redirect():
- Edit comments to better explain what the flag values do.
src/cmd/ksh93/bltins/misc.c:
- Add a dummy b_redirect() function declaration "for the dictionary
generator" as has historically been done for other builtins that
share one C function. I'm not sure what that dictionary generator
is supposed to be, but this also improves greppability.
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/sh.1:
- Fix misleading "I/O redirection arguments" term. I/O redirections
are not arguments at all; no argument parser ever sees them.
src/cmd/ksh93/tests/io.sh:
- Test both conditions that should make 'redirect' produce an
"incorrect syntax" error.
- Test that any redirections are not executed if erroneous
non-redirection arguments exist.
src/cmd/ksh93/tests/builtins.sh:
- "... should show usage info on unrecognized options" test:
Because 'redirect' now refuses to process redirections on error,
the error message was not captured. The fix is to run the builtin
in a braces block and add the redirection to the block.
The liblist variable needs to be an extern for dtksh to build.
Quote from CDE developer Chase:
we use an old function that no longer appears in kornshell,
sh_getliblist, it seems to be replaced by the function sh_getlib,
which is fine, but it seems to return a "Shbltin_f" type, which I
can't seem to find any information on what it is. We need the void
pointer dlsym provides for some widget init stuff, I tried making
liblist an extern, but it kept giving me an error about libcomp_t
being undefined.
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/include/shell.h:
- Fix the compiler error reported above by moving the type definition
for Libcomp_t to shell.h.
- Make liblist an extern since findsym.c in dtksh needs it to build.
The old sh_getliblist function doesn't need to be reintroduced
since the only purpose it served was to workaround the problem
of liblist being a static variable. Now that liblist is an extern,
dtksh fsym can use liblist directly to avoid sh_getliblist.
dtksh findsym.c:
https://sourceforge.net/p/cdesktopenv/code/ci/2.3.2/tree/cde/programs/dtksh/findsym.c
If an array or upper/lowercase variable was declared with a null
initial value within a virtual/non-forked subshell, like:
( typeset -a foo; ... )
( typeset -A foo; ... )
( typeset -l foo; ... )
( typeset -u foo; ... )
then the type declaration leaked out of the subshell into the
parent shell environment, though without any values that may
subsequently have been assigned.
src/cmd/ksh93/bltins/typeset.c: setall():
- When deciding whether to create a virtual subshell scope for a
variable, use sh_assignok(), which was actually designed for the
purpose, instead of _nv_unset(). This allows getting rid of a
tangled mess of special-casing that never worked quite right.
src/cmd/ksh93/tests/arrays.sh:
- Add regression tests checking that array declarations don't leak
out of virtual subshells.
src/cmd/ksh93/tests/attributes.sh:
- Add regression tests for combining the 'export' and 'readonly'
attributes with every other possible typeset attribute on unset
variables. This also includes a subshell leak test for each one.
Fixes: https://github.com/ksh93/ksh/issues/88
When a builtin is given an unrecognized option, the usage information
for that builtin should be shown as 'Usage: builtin-name options'. The
sleep and suspend builtins were an exception to this. 'suspend' would
not show usage information and sleep wouldn't exit on error:
$ suspend -e
/usr/bin/ksh: suspend: -e: unknown option
$ time sleep -e 1
sleep: -e: unknown option
real 0m1.00s
user 0m0.00s
sys 0m0.00s
src/cmd/ksh93/bltins/sleep.c:
- Show usage information and exit when sleep is given an unknown
option. This bugfix was backported from ksh2020: https://github.com/att/ast/pull/1024
src/cmd/ksh93/bltins/trap.c:
- Use the normal method of parsing options with optget to fix the
suspend builtin's test failure.
src/cmd/ksh93/tests/builtins.sh:
- Add the ksh2020 regression test for getting the usage information
of each builtin. Enable all /opt/ast/bin builtins in a subshell
since those should be tested as well (aside from getconf and uname
because those builtins fallback to the real commands on error).
'whence -a' is documented to list all possible interpretations of a
command, but failed to list a built-in command if a shell function
by the same name exists or is marked undefined using 'autoload'.
src/cmd/ksh93/bltins/whence.c: whence():
- Refactor and separate the code for reporting functions and
built-in commands so that both can be reported for one name.
src/cmd/ksh93/data/builtins.c: sh_optwhence[]:
- Correct 'whence --man' to document that:
* 'type' is equivalent to 'whence -v'
* '-a' output is like '-v'
src/cmd/ksh93/tests/builtins.sh:
- Test 'whence -a' with these combinations:
* a function, built-in and external command
* an undefined/autoload function, built-in and external command
Fixes https://github.com/ksh93/ksh/issues/83
$ ksh -c 'whence -a printf'
printf is a shell builtin
printf is /usr/bin/printf
printf is an undefined function
The third line should not appear.
src/cmd/ksh93/bltins/whence.c:
- Remove faulty extra check for undefined (= autoload) functions.
This was already handled earlier, on lines 192-193.
src/cmd/ksh93/tests/builtins.sh:
- Add regression test.
- For previous 'whence -a' test, don't bother with shell function.
Fixes https://github.com/ksh93/ksh/issues/26
This commit fixes two different crashes related to kshdb:
- When redirect is given an invalid file descriptor, a segfault
no longer occurs. Reproducer:
$ ksh -c 'redirect 9>&200000000000'
- Fix a crash due to free(3) being used on an invalid pointer.
This can be reproduced with kshdb (commands from att/ast#582):
$ git clone https://github.com/rocky/kshdb.git
$ cd kshdb
$ ksh autogen.sh
$ echo "print hi there" > $HOME/.kshdbrc
$ ./kshdb -L . test/example/dbg-test1.sh
src/cmd/ksh93/bltins/misc.c: b_dot_cmd():
- The string pointed to by shp->st.filename must be able to be
freed from memory with free(3), so duplicate the string with
strdup(3).
src/cmd/ksh93/sh/io.c: sh_redirect():
- Show an error message when a file descriptor is invalid to
fix a memory fault.
Commit 80d9ae2b removed the line that set the NV_EXPORT flag on an
alias when the obsolete ksh88 'alias -x' option was used. But it
turns out that flag actually did something: it caused 'whence -v'
to report the alias as an exported alias -- misleadingly, because
exported aliases have never actually exised in ksh93. Since '-x' no
longer sets that flag, that message is never printed.
src/cmd/ksh93/data/msg.c,
src/cmd/ksh93/include/path.h:
- Remove is_xalias[] = "%s is an exported alias for " message.
src/cmd/ksh93/bltins/whence.c:
- Remove dead code to check for (formerly) exported alias.
The coshell(1) command, which is required for libcoshell to be
useful, is not known to be shipped by any distribution. It was
removed by the ksh-community fork and hence also by 93u+m (in
2940b3f5). The coshell facility as a whole is obsolete and
insecure. For a long time now, the statically linked libcoshell
library has been 40+ kilobytes of dead weight in the ksh binary.
Prior discussion (ksh2020): https://github.com/att/ast/issues/619
src/lib/libcoshell/*:
- Removed.
src/cmd/ksh93/*:
- Remove the SHOPT_COSHELL compiler option (which was enabled) and
a lot of code that was conditional upon #ifdef SHOPT_COSHELL.
- init.c: e_version[]: Removing SHOPT_COSHELL changed the "J"
feature identifier in ${.sh.version} to a lowercase "j", which
was conditional upon SHOPT_BGX (background job extensions).
But src/cmd/ksh93/RELEASE documents (at 08-12-04, on line 1188):
| +SHOPT_BGX enables background job extensions. Noted by "J" in
| the version string when enabled. [...]
That is the only available documentation. So change that "j" back
to a "J", leaving the version string unchanged after this commit.
- jobs.c: job_walk(): We need to keep one 'job_waitsafe(SIGCHLD);'
call that was conditional upon SHOPT_COSHELL; removing it caused
a regression test failure in tests/sigchld.sh, 'SIGCHLD blocked
for script at end of pipeline' (which means that until now, a ksh
compiled without libcoshell had broken SIGCHLD handling.)
bin/package, src/cmd/INIT/package.sh:
- Don't export COSHELL variable.
Support for the long-dead 3DFS userland versioning file system was
already removed from ksh93 (although I'd overlooked some minor
things), but libast still supported it. This removes that too.
src/lib/libast/include/fs3d.h,
src/lib/libast/man/fs3d.3,
src/lib/libast/misc/fs3d.c:
- Removed.
bin/package,
src/cmd/INIT/package.sh:
- Remove attempted use of removed vpath builtin.
src/cmd/ksh93/*:
- Remove minor 3dfs vestiges.
src/lib/lib{ast,cmd,coshell}/*:
- Remove code supporting 3dfs.
This commit backports the main changes to sh_delay from ksh93v-
and ksh2020, which fixes the following bugs:
- Microsecond amounts of less than one millisecond are no longer
ignored. The following loop will now take a minimum of one
second to complete:
for ((i = 0; i != 10000; i++)) do
sleep PT100U
done
- 'sleep 30' no longer adds an extra 30 milliseconds to the total
amount of time to sleep. This bug is hard to notice since 30
milliseconds can be considered within the margin of error. The
only reason why longer delays weren't affected is because the old
code masked the bug when the interval is greater than 30 seconds:
else if(n > 30)
{
sleep(n);
t -= n;
}
This caused 'sleep -s' to break with intervals greater than 30
seconds, so an actual fix is used instead of a workaround.
- 'sleep -s' now functions correctly with intervals of more than
30 seconds as the new code doesn't need the old workaround. This
is done by handling '-s' in sh_delay.
src/cmd/ksh93/bltins/sleep.c:
- Remove the replacement for sleep(3) from the sleep builtin.
- Replace the old sh_delay function with the newer one from ksh2020.
The new function uses tvsleep, which uses nanosleep(3) internally.
src/cmd/ksh93/include/shell.h,
src/cmd/ksh93/edit/edit.c,
src/cmd/ksh93/sh/jobs.c,
src/cmd/ksh93/sh/xec.c,
src/cmd/ksh93/shell.3:
- Update sh_delay documentation and usage since the function now
requires two arguments.
src/cmd/ksh93/tests/builtins.sh:
- Add a regression test for 'sleep -s' when the interval is greater
than 30 seconds. The other bugs can't be tested for in a feasible
manner across all systems:
https://github.com/ksh93/ksh/pull/72#issuecomment-657215616
With this change no more preset aliases exist, so the preset alias
tables can be safely removed. All ksh commands can now be used
without 'unalias -a' removing them, even in interactive shells.
Additionally, the history and r commands are no longer limited to
being used in interactive shells.
src/cmd/ksh93/bltins/hist.c:
- Implement the history and r commands as builtins. Also guarantee
lflag is set to one by avoiding 'lflag++'.
src/cmd/ksh93/Makefile,
src/cmd/ksh93/Mamfile,
src/cmd/ksh93/sh/main.c,
src/cmd/ksh93/sh/init.c,
src/cmd/ksh93/data/aliases.c:
- Remove the table of predefined aliases because the last few have
been removed. During init the alias tree is now initialized the
same way as the function tree.
src/cmd/ksh93/bltins/typeset.c:
- Remove the bugfix for unsetting predefined aliases because it is
now a no-op. Aliases are no longer able to have the NV_NOFREE
attribute.
src/cmd/ksh93/tests/alias.sh:
- Remove the regression test for unsetting predefined aliases since
those no longer exist.
src/cmd/ksh93/data/builtins.c:
- Update sh_opthist[] for 'hist --man', etc.
src/cmd/ksh93/sh.1:
- Remove the list of preset aliases since those no longer exist.
- Document history and r as builtins instead of preset aliases.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
This converts the 'autoload', 'compound', 'float', 'functions',
'integer' and 'nameref' default aliases into regular built-in
commands, so that 'unalias -a' does not remove them. Shell
functions can now use these names, which improves compatibility
with POSIX shell scripts.
src/cmd/ksh93/data/aliases.c:
- Remove default typeset aliases.
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/include/builtins.h:
- Add corresponding built-in command declarations. Typeset-style
commands are now defined by a pointer range, SYSTYPESET ..
SYSTYPESET_END. A couple need their own IDs (SYSCOMPOUND,
SYSNAMEREF) for special-casing in sh/xec.c.
- Update 'typeset --man'.
src/cmd/ksh93/bltins/typeset.c: b_typeset():
- Recognise the new builtin commands by argv[0]. Implement them by
inserting the corresponding 'typeset' options into the argument
list before parsing options. This may seem like a bit of a hack,
but it is simpler, shorter, more future-proof and less
error-prone than manually copying and adapting all the complex
flaggery from the option parsing loop.
src/cmd/ksh93/sh/parse.c,
src/cmd/ksh93/sh/xec.c:
- Recognise typeset-style commands by SYSTYPESET .. SYSTYPESET_END
pointer range.
- Special-case 'compound' (SYSCOMPOUND) and 'nameref' (SYSNAMEREF)
along with recognising the corresponding 'typeset' options.
src/cmd/ksh93/sh.1:
- Update to document the new built-ins.
- Since not all declaration commands are special built-ins now,
identify declaration commands using a double-dagger "\(dd"
character (which renders as '=' in ASCII) and disassociate their
definition from that of special built-ins.
src/cmd/ksh93/tests/variables.sh:
- Adapt a regression test as there is no more 'integer' alias.
Now that we have an iffe feature test for getrusage(3), introduced
in 70fc1da7, the millisecond-precision 'times' command from the
last version of ksh2020 can easily be backported.
src/cmd/ksh93/bltins/misc.c:
- Incorporate ksh2020 'times' command, with a couple of tweaks:
* Use locale's radix point instead of '.'.
* Pad seconds with initial zero if < 10.
src/cmd/ksh93/data/builtins.c:
- Update version date for 'times --man'.
src/cmd/ksh93/tests/builtins.sh:
- Update 'times' test for 3 digits after radix point.
There is a bug in print_scan() function that may cause ksh to crash
while listing indexed arrays. The crash happens in nv_search() when
called from print_scan().
This applies a fix from Siteshwar Vashist:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01944.html
src/cmd/ksh93/bltins/typeset.c:
- Call nv_scan() without the NV_IARRAY flag, even for a null scan.
src/cmd/ksh93/tests/arrays.sh:
- Add regression test for 'typeset -a' crash and check output.
File descriptors that are too far out of range will cause the
read builtin to crash. The following example will generate
two crashes:
$ ksh -c 'read -u 2000000' || ksh -c 'read -u-2000000'
The fix is to error out when the given file descriptor is out
of range. This bugfix is from Tomas Klacko, although it was
modified to use 'sh_iovalidfd' and reject numbers greater
than 'INT_MAX':
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01912.html
The question about 'shp->fdstatus[-1]' only applies to ksh93v-
(ksh93u+ doesn't have any references to 'shp->fdstatus[-1]').
src/cmd/ksh93/bltins/read.c:
- File descriptors that are out of range should be rejected
with an error message (like invalid file descriptors that
are in range). The seemingly redundant check for negative
numbers is there because out of range negative numbers also
cause memory faults despite the later 'fd<0' check.
src/cmd/ksh93/tests/io.sh:
- Add three tests for attempting 'read -u' on various invalid
file descriptor numbers.
* Fix the readonly builtin's scope in functions
This bug was first reported at https://github.com/att/ast/issues/881
'tdata.sh->prefix' is only set to the correct value when
'b_readonly' is called as 'export', which breaks 'readonly' in
functions because the correct scope isn't set. As a result, the
following example will only print a newline:
$ function show_bar { readonly foo=bar; echo $foo; }; show_bar
The fix is to move the required code out of the if statement for
'export', as it needs to be run for 'readonly' as well. This bugfix
is from https://github.com/att/ast/pull/906
src/cmd/ksh93/bltins/typeset.c:
- Set 'tdata.sh->prefix' to the correct value, otherwise 'readonly'
uses the wrong scope.
src/cmd/ksh93/tests/builtins.sh:
- Add the regression test from ksh2020, modified to run in a
subshell.
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/sh.1:
- Add documentation of 'readonly' vs. 'typeset -r' difference:
'readonly' does not create a function-local scope.
Co-authored-by: Martijn Dekker <martijn@inlv.org>
The cd builtin was removing '.' from directory names when combined
with a preceding '../', which caused commands like 'cd ../.local'
to become 'cd ../local'. This patch fixes the problem by limiting
the extra handling to leading '..'. The bugfix comes from ksh93v-
2013-10-10-alpha, although this version is a shortened patch from
Solaris (as ksh93v- refactored a decent amount of the code for the
cd builtin).
src/cmd/ksh93/bltins/cd_pwd.c:
- cd should only check for leading '..', as trying to handle a lone
'.' only causes problems.
src/cmd/ksh93/tests/builtins.sh:
- Add a regression test for this problem based on the test present in
ksh93v- 2013-10-10-alpha.
Patch from Solaris:
860d27f/components/ksh93/patches/270-23319761.patch
Somewhat notable changes in this commit:
- The 'set +r' bugfix (re: 74b41621) is now documented in the
changelog.
- Missing options have been added to the synopsis section of the
ksh man page.
- The minor formatting fix from https://github.com/ksh-community/ksh/pull/5
has been applied to the ksh man page.
- A few fixes from 5e747cfb
have been applied to the ksh man page.
- The man page fixes from https://github.com/att/ast/pull/353
have been applied, being:
- An addition to document the behavior of 'set -H'.
- A fix for the cd section appending rksh93.
- A fix for some options being indented too far.
- Removal of a duplicate section documenting '-D'.
- Reordering the options for 'set' in alphabetical order.
- A minor fix for the documentation of 'ksh -i'.
The output format is now identical to mksh's except for
the locale-dependent radix point ('.' or ',').
src/cmd/ksh93/bltins/misc.c:
- Output format tweak: pad seconds with initial zero if < 10.
- Use "too many operands" (e_toomanyops) error msg from 3ba4900e
if there are operands, instead of "bad syntax" (e_badsyntax).
- Consolidate repetitive calculating and printing code
into print_times().
- Get rid of some excessive variables.
src/cmd/ksh93/tests/builtins.sh:
- Update regression tests to match the above.
src/cmd/ksh93/data/builtins.c:
- Update sh_opttimes[] version string.
Well, that's what I get for backporting code without properly
checking it over. There was an elementary math error in how the
times builtin calculated seconds:
utime_sec = utime - utime_min;
which could cause output such as "1m98.38s" or "3m234.77s".
src/cmd/ksh93/bltins/misc.c: b_times():
- Use fmod(), i.e. floating point modulus, to calculate seconds.
The 'stop' and 'suspend' default aliases are now converted into
regular built-in commands so that 'unalias -a' does not remove
them, 'suspend' can do some sanity checks, and something like
cmd=stop; $cmd $!
will now work.
src/cmd/ksh93/bltins/trap.c:
- b_kill(): Incorporate 'stop' functionality, which is simply
setting the same flag and variable as '-s STOP' would have done.
- b_suspend(): Add simple builtin function that sends SIGSTOP to
the main shell. Check for no operands, and refuse to suspend a
login shell (which would leave the user stuck with no way out).
Also check that 'kill' succeeds; if we're in an asynchronous
subshell, it is possible the main shell no longer exists.
src/cmd/ksh93/data/aliases.c:
- Remove "stop" and "suspend" default aliases. (Why were these
conditional upon SIGTSTP when they actually issued SIGSTOP?)
src/cmd/ksh93/include/builtins.h,
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/data/msg.c:
- Add declarations of "stop" and "suspend" regular built-ins.
- Add option strings (AST manual/--man pages) for them.
- Add e_toomanyops ("too many operands") reusable error message for
b_suspend(). Other new commands may want this at some point.
src/cmd/ksh93/sh.1:
- Remove "stop" and "suspend" default aliases.
- Document "stop" and "suspend" regular built-in commands.
src/cmd/ksh93/data/variables.c:
- Running 'unset .sh.lineno' creates a memory fault, so fix that
by giving it the NV_NOFREE attribute. This crash was happening
because ${.sh.lineno} is an integer that cannot be freed from
memory with free(3).
src/cmd/ksh93/sh/init.c:
- Tell _nv_unset to ignore NV_RDONLY when $RANDOM and $LINENO are
restored from the subshell scope. This is required to fully
restore the original state of these variables after a virtual
subshell finishes.
src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/sh/subshell.c:
- Disabled some optimizations for two instances of 'sh_assignok' to
fix 'readonly' in virtual subshells and '(unset .sh.level)' in
nested functions. This fixes the following variables when
'(readonly $varname); enum varname=' is run:
$_
${.sh.name}
${.sh.subscript}
${.sh.level}
The optimization in question prevents sh_assignok from saving the
original state of these variables by making the sh_assignok call
a no-op. Ksh needs the original state of a variable for it to be
properly restored after a virtual subshell has run, otherwise ksh
will simply carry over any new flags (being NV_RDONLY in this case)
from the subshell into the main shell.
src/cmd/ksh93/tests/variables.sh:
- Add regression tests from Martijn Dekker for setting special
variables as readonly in virtual subshells and for unsetting
special variables in general.
Fixes#4
'whence -a' bases the path for tracked aliases on the user's
current working directory if an enabled ksh builtin of the same
name is also available. The following example will claim 'cat'
is in the user's current working directory:
$ whence -a cat
cat is a tracked alias for /usr/bin/cat
$ builtin cat
$ whence -a cat
cat is a shell builtin
cat is /usr/bin/cat
cat is a tracked alias for /current/working/directory/cat
This patch from ksh2020 fixes this problem by properly saving the
path of the tracked alias for use with 'whence -a', since
'path_pwd' (as implied by the function's name) only gets the users
current working directory, not the location of tracked aliases.
Ref.: https://github.com/att/ast/issues/1049
This bug was originally reported by David Morano about two decades
ago to the AST team: https://github.com/att/ast/issues/954
src/cmd/ksh93/bltins/whence.c:
- Print the actual path of a tracked alias, path_pwd doesn't
have this functionality.
src/cmd/ksh93/include/name.h:
- Add 'pathcomp' for saving the value of tracked aliases.
src/cmd/ksh93/sh/path.c:
- Save the value of tracked aliases for use by whence.
src/cmd/ksh93/tests/builtins.sh:
- Add a regression test for using 'whence -a' on tracked
aliases with a builtin equivalent.
This bug was previously reported in att/ast#37.
Ksh ignores `-r` when `read -r -d` is run because when
the bit for `D_FLAG` is set, the bit for `R_FLAG` is unset
as a side effect of setting `D_FLAG`. The following set
of commands fails to print a backslash:
$ printf '\\\000' | read -r -d ''
$ echo $REPLY
The fix for this bug is to set `D_FLAG` with `D_FLAG + 1`,
which prevents `R_FLAG` from being unset. This bugfix
has been backported from ksh93v- 2013-10-10-alpha.
src/cmd/ksh93/bltins/read.c:
- Set `D_FLAG` with `D_FLAG + 1` to prevent the bit for
`R_FLAG` from being unset.
src/cmd/ksh93/tests/builtins.sh:
- Add the regression test for `read -r -d` from ksh93v-.
