bug#53801: [PATCH] tests: have printf(1) use octal numbers for POSIX conformance
Hi Brian, On Mon, 7 Feb 2022 08:52:29 -0800 "Brian C. Lane" wrote: > On Sat, Feb 05, 2022 at 10:44:29AM +, Kerin Millar wrote: > > Hello, > > > > The attached patch rectifies some test failures that were reported at > > https://bugs.gentoo.org/774363. Whether it be a builtin of sh(1) or not, > > POSIX does not require for the printf utility to support hexadecimal > > notation. > > > > -- > > Kerin Millar > > Thanks for the patch. I'll have to ponder this for a bit. So the issue > is showing up in Gentoo because it uses dash, right? The issue I have > with the change is that it then obscures what's being written. Everyone > knows what 0x55aa is :) I'd prefer a solution that continues to use hex > so that future users don't have to figure out what's going on. In fact, Gentoo provides bash as a default sh(1) implementation, by which I mean that /bin/sh begins life as being a symlink to bash. Still, that's neither here nor there. The policy of the distro is that the user may select another sh(1) provider, as long as it is POSIX-conforming. Dash is merely one such example of a shell that implements the Shell Command Language specification correctly and in full. Should an issue arise as a consequence of /bin/sh being any conforming implementation other than bash, it is rightly treated as a bug. Often, patches are proposed and the more responsible contributors try to get them upstreamed so that everyone benefits. Of course, there exists other distributions where /bin/sh is some other implementation by default. Essentially, this is one of those cases where one cannot have one's cake and eat it. By beginning a script with a shebang that reads #!/bin/sh, it is implied - in no uncertain terms - that the entirety of the script should run correctly in any conforming implementation of the Shell Command Language. In almost all modern implementations, the printf utility is implemented as a builtin and their authors are in no way obligated to implement anything above and beyond the syntax described by https://pubs.opengroup.org/onlinepubs/9699919799/utilities/printf.html. While bash is - at heart - a valid implementation of the Shell Command Language, it supports a great many extensions and does not suppress them, even when running in its "posix" mode. In fact, this is not the first time this issue has come up; see "t0100-print.sh" and "t0251-gpt-unicode.sh". I understand that most developers will find hex notation easier to read, which is why my patch also adjusts the surrounding commentary to that end. In my view, the alternatives are worse:- a) changing the shebangs to #!/bin/bash, rendering bash a hard requirement for running the affected tests (merely for a printf) b) combining arithmetic expansion with printf Regarding (b), below is an example. # Write the two magic bytes magic=$(printf '\\%03o' $(( 0x55 )) $(( 0x0A ))) printf "$magic" | ... Not only is this more expensive, one might then need to be cautious as to the potential matter of unintentionally injecting the results of expansions into the format string, owing to the double-quoted context. I certainly wouldn't consider it to be any easier to digest than the following. # Write the two magic bytes, 0x55 0xAA. printf '\125\252' | ... Incidentally, octal is trivial to convert to peruse as hex using only standard utilities. $ printf '\125\252' | od -An -t x1 55 aa Regards, -- Kerin Millar
bug#53801: [PATCH] tests: have printf(1) use octal numbers for POSIX conformance
On Mon, 7 Feb 2022 09:10:12 -0800 "Brian C. Lane" wrote: > On Mon, Feb 07, 2022 at 08:52:33AM -0800, Brian C. Lane wrote: > > On Sat, Feb 05, 2022 at 10:44:29AM +, Kerin Millar wrote: > > > Hello, > > > > > > The attached patch rectifies some test failures that were reported at > > > https://bugs.gentoo.org/774363. Whether it be a builtin of sh(1) or not, > > > POSIX does not require for the printf utility to support hexadecimal > > > notation. > > > > > > -- > > > Kerin Millar > > > > Thanks for the patch. I'll have to ponder this for a bit. So the issue > > is showing up in Gentoo because it uses dash, right? The issue I have > > with the change is that it then obscures what's being written. Everyone > > knows what 0x55aa is :) I'd prefer a solution that continues to use hex > > so that future users don't have to figure out what's going on. > > Actually, on Fedora at least, printf comes from coreutils so the shell > shouldn't matter at all. The tests are single quoted to prevent shell > expansion, so maybe dash is using a builtin printf that's different? $ bash -c 'type printf' printf is a shell builtin Yes, it's also a builtin in dash (it is rare these days for printf to ever be invoked in its capacity as a binary). As explained by my prior message, no implementation of the POSIX shell and utilities (XCU) is under any obligation to support GNU-specific features. Therein lies the rub. Octal sequences are guaranteed to work. The problem is a great many Linux developers only ever test things in bash, even where their shebangs purport to target sh. -- Kerin Millar
bug#53858: Errors in man pages of parted
Dear parted maintainer, the manpage-l10n project maintains a large number of translations of man pages both from a large variety of sources (including parted) as well for a large variety of target languages. During their work translators notice different possible issues in the original (english) man pages. Sometimes this is a straightforward typo, sometimes a hard to read sentence, sometimes this is a convention not held up and sometimes we simply do not understand the original. We use several distributions as sources and update regularly (at least every 2 month). This means we are fairly recent (some distributions like archlinux also update frequently) but might miss the latest upstream version once in a while, so the error might be already fixed. We apologize and ask you to close the issue immediately if this should be the case, but given the huge volume of projects and the very limited number of volunteers we are not able to double check each and every issue. Secondly we translators see the manpages in the neutral po format, i.e. converted and harmonized, but not the original source (be it man, groff, xml or other). So we cannot provide a true patch (where possible), but only an approximation which you need to convert into your source format. Finally the issues I'm reporting have accumulated over time and are not always discovered by me, so sometimes my description of the problem my be a bit limited - do not hesitate to ask so we can clarify them. I'm now reporting the errors for your project. If future reports should use another channel, please let me know. Man page: parted.8 Issue:B → B(1) "B(8), B(8), The I program is fully documented in the " "B format I manual." -- Man page: parted.8 Issue:B → B(1) "B(8), B(8), The I program is fully documented in the " "B format I manual which is distributed " "with the parted-doc Debian package." -- Dr. Helge Kreutzmann deb...@helgefjell.de Dipl.-Phys. http://www.helgefjell.de/debian.php 64bit GNU powered gpg signed mail preferred Help keep free software "libre": http://www.ffii.de/ signature.asc Description: PGP signature
bug#53801: [PATCH] tests: have printf(1) use octal numbers for POSIX conformance
On Mon, Feb 07, 2022 at 08:52:33AM -0800, Brian C. Lane wrote: > On Sat, Feb 05, 2022 at 10:44:29AM +, Kerin Millar wrote: > > Hello, > > > > The attached patch rectifies some test failures that were reported at > > https://bugs.gentoo.org/774363. Whether it be a builtin of sh(1) or not, > > POSIX does not require for the printf utility to support hexadecimal > > notation. > > > > -- > > Kerin Millar > > Thanks for the patch. I'll have to ponder this for a bit. So the issue > is showing up in Gentoo because it uses dash, right? The issue I have > with the change is that it then obscures what's being written. Everyone > knows what 0x55aa is :) I'd prefer a solution that continues to use hex > so that future users don't have to figure out what's going on. Actually, on Fedora at least, printf comes from coreutils so the shell shouldn't matter at all. The tests are single quoted to prevent shell expansion, so maybe dash is using a builtin printf that's different? Brian -- Brian C. Lane (PST8PDT) - weldr.io - lorax - parted - pykickstart
bug#53801: [PATCH] tests: have printf(1) use octal numbers for POSIX conformance
On Sat, Feb 05, 2022 at 10:44:29AM +, Kerin Millar wrote: > Hello, > > The attached patch rectifies some test failures that were reported at > https://bugs.gentoo.org/774363. Whether it be a builtin of sh(1) or not, > POSIX does not require for the printf utility to support hexadecimal notation. > > -- > Kerin Millar Thanks for the patch. I'll have to ponder this for a bit. So the issue is showing up in Gentoo because it uses dash, right? The issue I have with the change is that it then obscures what's being written. Everyone knows what 0x55aa is :) I'd prefer a solution that continues to use hex so that future users don't have to figure out what's going on. Brian -- Brian C. Lane (PST8PDT) - weldr.io - lorax - parted - pykickstart
