This allows scripts to check for a nonzero exit status on the 'print', 'printf' and 'echo' builtins and prevent possible infinite loops if SIGPIPE is ignored. sfsync() was already returning a negative value on I/O error, so all we need to do is add a check. The stream buffer will need to be filled before an I/O error can be detected, but this is the same on other shells. See manual page: src/lib/libast/man/sfio.3 Ref.: https://github.com/att/ast/issues/1093 https://github.com/att/ast/pull/1363 src/cmd/ksh93/bltins/print.c: b_print(): - Make sure an error result from sfsync() is reflected in the output builtin's exit status (exitval). - Write an I/O error message (e_io) if the exit status is nonzero. src/cmd/ksh93/data/msg.c, src/cmd/ksh93/include/io.h: - Add the e_io[] error message. src/cmd/ksh93/tests/builtins.sh: - Add I/O error regression test, checking for the correct error message and exit status. All three output builtins use the same b_print() function so we only need to test one. src/cmd/ksh93/tests/basic.sh, src/cmd/ksh93/tests/coprocess.sh: - Redirect stderr on a few 'print' commands to /dev/null; these now issue an expected I/O error. This does not cause failures. NEWS, TODO: - Update. (cherry picked from commit 9011fa933552e483dab460f7dd1593d64e059d94) |
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bin | ||
docs | ||
lib/package | ||
src | ||
.gitignore | ||
LICENSE.md | ||
NEWS | ||
README.md | ||
TODO |
KornShell 93u+m
This repository is used to develop bugfixes to the last stable release (93u+ 2012-08-01) of ksh93, formerly developed by AT&T Software Technology (AST). The sources in this repository were forked from the Github AST repository which is no longer under active development.
To see what's fixed, see NEWS and click on commit messages for full details.
To see what's left to fix, see TODO.
Policy
- No new features. Bug fixes only.
- No major rewrites. No refactoring code that is not fully understood.
- No changes in documented behaviour, except if required for compliance with the POSIX shell language standard which David Korn intended for ksh to follow.
- No 100% bug compatibility. Broken and undocumented behaviour gets fixed.
- No bureaucracy, no formalities. Just fix it, or report it: create issues, send pull requests. Every interested party is invited to contribute.
- To help increase everyone's understanding of this code base, fixes and significant changes should be fully documented in commit messages.
Why?
Between 2017 and 2020 there was an ultimately unsuccessful attempt to breathe new life into the KornShell by extensively refactoring the last unstable AST beta version (93v-). While that ksh2020 branch is now abandoned and still has many critical bugs, it also had a lot of bugs fixed. More importantly, the AST issue tracker now contains a lot of documentation on how to fix those bugs, which makes it possible to backport many of them to the last stable release instead.
In February 2020, having concluded the AST 93v- beta was too broken to base new work on, others decided to start a new fork based on the last stable 93u+ 2012-08-01 release. Unfortunately, as of June 2020, the new ksh-community organisation is yet to see any significant activity four months after its bootstrapping. I hope that will change; I am ready to join efforts with them at any time, as well as anyone else who wants to contribute.
The last stable ksh93 release from 2012 is the least buggy release currently available, but it still has many serious bugs. So it is well past time to start fixing those bugs, leave the rest of the code alone, and get an improved release out there.
Build
After cloning this repo, cd to the top directory of it and run:
./bin/package make
If you have trouble or want to tune the binaries, you may pass additional compiler and linker flags by appending it to the command shown above. E.g.:
./bin/package make \
SHELL=/bin/bash CCFLAGS="-xc99 -D_XPG6 -m64 -xO4" LDFLAGS="-m64"
For more information run
bin/package help
Many other commands in this repo self-document via the --help
, --man
and
--html
options; those that do have no separate manual page.
Test
After compiling, you can run the regression tests. Start by reading the information printed by:
./bin/shtests --man