Re: printf doesn't zero-pad strings

[Wolfgang Laun]

Both the gawk User Manual and "man -s 3 printf" document that the modifier
"0" only applies to numeric formats, which   "%s" most certainly is not.
This is a feature simply taken over from C and implemented using its
library.
-W

On Fri, 11 Aug 2023 at 07:45, tink <tink.lq@gmail.com> wrote:

> Configuration Information [Automatically generated, do not change]:
> Machine: aarch64
> OS: darwin22.4.0
> Compiler: clang
> Compilation CFLAGS: -g -O2 -DNDEBUG
> uname output: Darwin m1 22.6.0 Darwin Kernel Version 22.6.0: Wed Jul  5
> 22:22:52 PDT 2023; root:xnu-8796.141.3~6/RELEASE_ARM64_T8103 arm64
> Machine Type: aarch64-apple-darwin22.4.0
>
> Gawk Version: 5.2.2
>
> Attestation 1:
>   I have read https://www.gnu.org/software/gawk/manual/html_node/Bugs.html
> .
>   Yes
>
> Attestation 2:
>   I have not modified the sources before building gawk.
>   True
>
> Description:
>   gawk doesn't zero-pad strings when using printf - it emits a space
> instead.
>   I can confirm the same behaviour on Ubuntu, using a slightly older
> gawk, GNU Awk 5.0.1, API: 2.0 (GNU MPFR 4.0.2, GNU MP 6.2.0). The gawk
> above was installed via brew.
> The awk that ships w/ MacOS does the right thing, as does the one shipping
> with OpenBSD 7.2.
>
> (The Mac awk has no version info, but the man-page dates from 2020-11-24)
> andrej@m1:~/tmp8$ echo a |awk '{printf "%02s\n", $1}'
> 0a
>
> andrej@blowfish:~ $ awk -V
> awk version 20220912
> andrej@blowfish:~ $ echo a|awk '{printf "%02s\n", $1}'
> 0a
> andrej@blowfish:~ $
>
>
> Repeat-By:
>  $ LC_ALL=C echo a |gawk '{printf "%02s\n", $1}'
>  a
>
>
>
> --
>
> A: Because it messes up the order in which people normally read text.
> Q: Why is top-posting such a bad thing?
> A: Top-posting.
> Q: What is the most annoying thing in e-mail?
>


-- 
Wolfgang Laun