Apparently the person for whom the `-` works in gawk 4.2.1 also sees it
working in gawk 5.3.0, see:
https://imgur.com/a/YtgCkA6
They are testing on a Mac while I tested on 2 different laptops, both
running Windows 11, one in cygwin and the other git bash, so I'm
guessing this is something to do with underlying primitives. It's odd to
me that `date` behaves differently from `gawk` in this regard but I
guess it's just implemented differently. FWIW perl behaves the same way
as gawk:
$ cat tst.prl
#!/usr/bin/perl
use POSIX qw(strftime);
# Modules used
use strict;
use warnings;
# Print function
printf("Without -: %s\n", strftime "%m", localtime);
printf("With -:%s\n", strftime "%-m", localtime);
$ ./tst.prl
Without -: 01
With -:
$
and so does python:
$ cat tst.py
#!/usr/bin/python
from datetime import datetime
now = datetime.now()
print("Without -:", now.strftime("%m"))
print("With -:", now.strftime("%-m"))
$ ./tst.py
Without -: 01
With -:
Assuming it's not something that can/should be made to work portably,
maybe it's worth a brief note in the documentation that this is a thing,
just like the underlying primitives impact on rounding and reading
binary files are described elsewhere in the docs?
Ed.
On 1/27/2024 6:56 AM, Ed Morton wrote:
Someone posted an answer at
https://stackoverflow.com/a/77884684/1745001 that puts a `-` in front
of `strftime()` format specifiers to remove leading `0`s so that, for
example, we can print the month number by doing:
awk 'BEGIN{print strftime("%-m")}'
and get `1` output instead of the `01` we'd get with
awk 'BEGIN{print strftime("%m")}'
That's consistent with how GNU date (and apparently various other
tools) works:
$ date +'%-m'
1
$
$ date +'%m'
01
$
and it's what that SO answer shows with gawk 4.2.1.
When I try to do the same with gawk 5.0.0 or later, though, then I get:
$ awk 'BEGIN{print strftime("%-m")}'
$
$ awk 'BEGIN{print strftime("%m")}'
01
$
i.e. adding the `-` makes `strftime()` produce no output.
That functionality isn't documented in the manual best I can tell - is
that functionality that was removed or is it breakage or something else?
Ed.