GNU Awk 5.0

http://lists.gnu.org/archive/html/info-gnu/2019-04/msg00002.html

by Aissen • 7 years ago

229 48 7 years ago

lists.gnu.org

indeyets• 7 years ago

Release notes are a bit weird. It's like an author is shy of actual major changes: NAMESPACES and hides them behind mentions of c99 compliance and test infrastructure :-/

acqq4• 7 years ago

I would rather say “who asked for namespaces in awk”?

Who needs that and what’s the point? Any compatibility breakage in awk should start wit “negative points” so what are the positive ones to even qualify it as desired?

rwbhn• 7 years ago

See http://www.skeeve.com/awk-sys-prog.html

Bootvis• 7 years ago

It seems to have some breaking changes and non-user facing improvements though. I'm not sure major changes are needed but it should allow them more easily now.

fredsanford• 7 years ago

Arnold Robbins is a busy dude. He maintains awk, bash, gnu grep and several other must have packages.

A little slack would be nice.

OskarS• 7 years ago

Wow, I had no idea those things were maintained by the same guy! That's amazing! Is there somewhere one can contribute to his development efforts? I guess just donate to GNU Foundation?

BlackFingolfin• 7 years ago

Actually, Chet Ramey maintains GNU Bash, and Jim Meyering maintains GNU Grep. As far as I can tell, Arnold Robbins "just" maintains GNU awk. Don't get me wrong, I don't want to trivialize this at all, just correct the record.

clan• 7 years ago

How so? It is actually one of the very first things mentioned:

This is a major new release, with new or improved features, including namespaces. The relevant part of the NEWS file is appended below.

So you would be happier to have the item as number 1 rather than 11 in the list further down?

11. Namespaces have been implemented! See the manual. One consequence of this is that files included with -i, read with -f, and command line programsegments must all be self-contained syntactic units. E.g., you can no longer do something like this:

         gawk -e 'BEGIN {' -e 'print "hello" }'

I found the announcement rather concise and to the point.

Apart from that it would have been nice with a reference to what section of the manual to look at. Especially as https://www.gnu.org/software/gawk/manual/ still references 4.2 (will probably be updated soon).

vesinisa• 7 years ago

Perhaps the changes were listed in the chronological order of version control history, as is often the case with release notes, as opposed to any subjective notion like significance.

jph• 7 years ago

Congratulations and thank you! Namespaces are a big help for me personally.

From the GNU Awk 5 manual: A qualified name consists of a two simple identifiers joined by a double colon (::). The left-hand identifier represents the namespace and the right-hand identifier is the variable within it.

Namespaces are a big help for writing libraries, especially for clients with systems (e.g. banking, government, education, medical) where awk code is fine yet other kinds of languages (e.g. python, go, perl) are not available and/or require management audit practices.

koolba• 7 years ago

Why would awk not require audit and code management practices vs those other languages in a controlled environment?

timClicks• 7 years ago

Probably because awk is available as a stock build of the approved OS. It's been around a long time. I mean, to be POSIX-compliant, you need an awk interpreter in your system https://pubs.opengroup.org/onlinepubs/9699919799/utilities/a...

ivanbakel• 7 years ago

I took it to mean that getting support for those languages would require management audit practices i.e. "why are we installing a new package on all of our servers?". In that case, awk would be better since the gnutils are much more likely to already be installed and in use. The resulting awk code would still probably fall under code management.

acqq4• 7 years ago

Thanks for pointing to the Awk 5 manual (in the tar archive, I haven't seen it online still).

I've written the previous comment asking "why namespaces based" only on the directly online accessible info. Now having had the time to download and unpack the sources and read the documentation there, it sounds much better than it appeared based on the announcement.

Long term it shouldn't make gawk less compatible than it already is. Gawk already has gawk-specific extensions, and that would be one. It seems that the command-line example is the only "breaking" aspect. And even that could be theoretically modified to be non breaking, but it's hopefully seldom enough used to not affect too much.

And the "namespaces" is in fact a "module" infrastructure extension, introduced specifically to support the construction of module-like libraries (specifically solving the problem of exporting the limited number of variables from the module).

I especially like the writing of the author of Gawk manual, I've really enjoyed it even almost thirty years ago.

fs111• 7 years ago

I remember the days when I was working in a data company and one of the product check tools was a 2000 line GNU awk script with some korn shell in the mix. It was both scary and awesome at the same time..

stevekemp4• 7 years ago

In 2016 I fuzzed awk and found a bunch of segfaults. Sadly it seems still not fixed:

      $ ./bin/gawk -V | head -n 1
      GNU Awk 5.0.0, API: 2.0

      $ ./bin/gawk 'for (i = ) in steve kemp rocks'
      gawk: cmd. line:1: for (i = ) in steve kemp rocks
      gawk: cmd. line:1: ^ syntax error
      gawk: cmd. line:1: for (i = ) in steve kemp rocks
      gawk: cmd. line:1:          ^ syntax error
      gawk: cmd. line:1: fatal error: internal error
      Aborted (core dumped)

I'll have to forward bugs from the Debian-tracker to the maintainers directly I guess.

neilwilson• 7 years ago

I don't know Steve. Can't leave you alone with anything :-)

Nicely found!

zerr• 7 years ago

Did you try to contact directly Alfred, Peter or Brian? :)

stevekemp4• 7 years ago

I reported to the Debian bug-tracker where I assumed it would either be forwarded upstream, or be searched by the project authors:

https://bugs.debian.org/816277

I appreciate that most of the time reporting directly is the right thing to do, but often there is a good relationship between packager and developer and things flow well in both directions.

I guess I should make sure I chase old reports and reroute if they seem to be orphaned/ignored/overlooked.

aquamo• 7 years ago

Congrats! Long live {,g}awk !

tyingq• 7 years ago

Assuming the syntax is $name::spaces it could look like Awk borrowed something from Perl, which is a funny full circle.

nrclark• 7 years ago

I wonder if the new namespaces functionality will break compatibility for users. I guess I always assumed gawk was feature-complete, or at least a mature enough tool that I wouldn't expect compatibility breaks.

    11. Namespaces have been implemented! See the manual.  One consequence of this
        is that files included with -i, read with -f, and command line program
        segments must all be self-contained syntactic units. E.g., you can no
        longer do something like this:
    
            gawk -e 'BEGIN {' -e 'print "hello" }'

charlesdaniels• 7 years ago

It's not entirely clear, but I believe that some of these changes, namely namespacing, may impact compatibility with POSIX awk[1] (as shipped on BSD, macOS, etc. al.). Historically, GNU awk has been a strict superset of "standard" awk. I for one am concerned that this may impact portability of awk based scripts between platforms using gawk and other implementations.

It could be that I have missed a detail and this isn't really the case; I also certainly don't want to discourage progress, but there is something to be said for being able to write an awk program once and be confident it will work on any POSIX-ish system, rather than only those with a GNU userland.

1 - http://pubs.opengroup.org/onlinepubs/9699919799.2018edition/

dontbenebby2• 7 years ago

Does anyone know a good awk tutorial or book?

I kind of skipped over it in my journey into the world of Unix... I usually either (bash shell scripting, tools like cut and grep + pipes and redirection) or use python.

fooblitzky• 7 years ago

_The AWK Programming Language_ ( https://smile.amazon.com/AWK-Programming-Language-Alfred-Aho... ) is one of the best programming books, on any language, in my opinion. Worth reading even if you don't use awk. In less than 200 pages it covers an introduction to the language, through to implementing a relational database, recursive-descent parsing, and graph-based algorithms.

For gawk, the manual covers the gaps between the language introduced in the book and the latest implementation.

brians• 7 years ago

https://news.ycombinator.com/item?id=13451454

The Aho and Kernighan book is amazing.

noufalibrahim• 7 years ago

I have a rule of thumb that I'll buy and read any book which Kernighan is an author of regardless of subject. He's more or less the gold standard of technical writing for me.

dontbenebby2• 7 years ago

Cool, thanks for the suggestion! Are the basics pretty much unchanged? I see that edition is from 1988. I like free stuff, but I don't mind paying if you think a more recent edition is worth the $.

burgerdev• 7 years ago

The 6 page summary in the 7th edition manual turned out to be comprehensive while still being approachable. I knew next to nothing about awk, not counting some snippets found on the web, after reading through this document twice awk feels like home.

https://9p.io/7thEdMan/v7vol2b.pdf (starting on page 105)

microtherion• 7 years ago

Amazing how long gawk has been around, and still with the same maintainers.

My port of gawk to MacOS in 1990/91 was my first active involvement in open source. I was rather crushed when told that my patches would not get accepted, because RMS at the time had a Fatwa against accepting MacOS code in GNU projects, and, though the gawk maintainers were quite civil about it, it was clear that they would not go against RMS' wishes.

Shortly afterward I discovered perl, so I never did all that much awk, and when a few years ago, I decided a 5 line awk script was the most elegant way to solve a configuration problem, my coworkers vetoed the plan.

purplezooey• 7 years ago

Differences from gawk 4.2.1 are not available; they would be too large.

That's my kind of changelog. I, too like to live dangerously.

rhabarba• 7 years ago

Bug reports should be sent to address@hidden

Will do.

GNU Awk 5.0

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