99f6a43296
printstat and awkprintf are very clear: print statement errors are fatal. In Jan 2020 [1], to prevent fatal print errors from masquerading as fclose warnings, every WARNING in closefile and closeall became FATAL. This broke awk's close and getline functions. close no longer returns if there's an error, unless the stream doesn't exist. getline read errors still return -1, but they are no longer ignorable. Eventually, one of the closing functions will inspect the stream with ferror and call FATAL. In Jul 2020 [2], fatal stdout write errors which had been detectable by closefile for a few months became invisible, a consequence of switching standard streams from fclose (which reports flush errors) to freopen (which ignores them). The Jan 2020 changes which broke getline and close were themselves partially broken. The solution is to finish printing before closing. That is to flush and ferror every stream opened for writing before calling fclose, pclose, or freopen. A failure to write print statement data is fatal. A failure to close a flushed stream is a warning. They must be handled separately. Every redirected print statement is finished in printstat or awkprintf. The same is not true of unredirected print statements. To finish these, stdout must be flushed at some point after the final such statement. Any problem with that flush is fatal. Though only stdout needs it, let's defensively finish every stream opened for writing, so this bug won't recur if someone changes how redirected streams are flushed. Write errors on stderr by the implementation are never fatal. When closing, we only warn of them. Write errors from an application attempting a redirected print to /dev/stderr are as immediately fatal as every other redirected print statement. [1] |
||
|---|---|---|
| bugs-fixed | ||
| testdir | ||
| .gitignore | ||
| ChangeLog | ||
| FIXES | ||
| LICENSE | ||
| README.md | ||
| REGRESS | ||
| TODO | ||
| awk.1 | ||
| awk.h | ||
| awkgram.y | ||
| b.c | ||
| lex.c | ||
| lib.c | ||
| main.c | ||
| makefile | ||
| maketab.c | ||
| parse.c | ||
| proto.h | ||
| run.c | ||
| tran.c | ||
README.md
The One True Awk
This is the version of awk described in The AWK Programming Language,
by Al Aho, Brian Kernighan, and Peter Weinberger
(Addison-Wesley, 1988, ISBN 0-201-07981-X).
Copyright
Copyright (C) Lucent Technologies 1997
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that the copyright notice and this permission notice and warranty disclaimer appear in supporting documentation, and that the name Lucent Technologies or any of its entities not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission.
LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
Distribution and Reporting Problems
Changes, mostly bug fixes and occasional enhancements, are listed
in FIXES. If you distribute this code further, please please please
distribute FIXES with it.
If you find errors, please report them to bwk@cs.princeton.edu. Please also open an issue in the GitHub issue tracker, to make it easy to track issues. Thanks.
Submitting Pull Requests
Pull requests are welcome. Some guidelines:
-
Please do not use functions or facilities that are not standard (e.g.,
strlcpy(),fpurge()). -
Please run the test suite and make sure that your changes pass before posting the pull request. To do so:
- Save the previous version of
awksomewhere in your path. Call itnawk(for example). - Run
oldawk=nawk make check > check.out 2>&1. - Search for
BADorerrorin the result. In general, look over it manually to make sure there are no errors.
- Save the previous version of
-
Please create the pull request with a request to merge into the
stagingbranch instead of into themasterbranch. This allows us to do testing, and to make any additional edits or changes after the merge but before merging tomaster.
Building
The program itself is created by
make
which should produce a sequence of messages roughly like this:
yacc -d awkgram.y
conflicts: 43 shift/reduce, 85 reduce/reduce
mv y.tab.c ytab.c
mv y.tab.h ytab.h
cc -c ytab.c
cc -c b.c
cc -c main.c
cc -c parse.c
cc maketab.c -o maketab
./maketab >proctab.c
cc -c proctab.c
cc -c tran.c
cc -c lib.c
cc -c run.c
cc -c lex.c
cc ytab.o b.o main.o parse.o proctab.o tran.o lib.o run.o lex.o -lm
This produces an executable a.out; you will eventually want to
move this to some place like /usr/bin/awk.
If your system does not have yacc or bison (the GNU
equivalent), you need to install one of them first.
NOTE: This version uses ANSI C (C 99), as you should also. We have
compiled this without any changes using gcc -Wall and/or local C
compilers on a variety of systems, but new systems or compilers
may raise some new complaint; reports of difficulties are
welcome.
This compiles without change on Macintosh OS X using gcc and
the standard developer tools.
You can also use make CC=g++ to build with the GNU C++ compiler,
should you choose to do so.
The version of malloc that comes with some systems is sometimes
astonishly slow. If awk seems slow, you might try fixing that.
More generally, turning on optimization can significantly improve
awk's speed, perhaps by 1/3 for highest levels.
A Note About Releases
We don't do releases.
A Note About Maintenance
NOTICE! Maintenance of this program is on a ''best effort'' basis. We try to get to issues and pull requests as quickly as we can. Unfortunately, however, keeping this program going is not at the top of our priority list.
Last Updated
Sat Jul 25 14:00:07 EDT 2021