* [9fans] how to output NUL byte from awk?
@ 2013-09-17 13:47 dexen deVries
2013-09-17 14:03 ` Kurt H Maier
` (2 more replies)
0 siblings, 3 replies; 11+ messages in thread
From: dexen deVries @ 2013-09-17 13:47 UTC (permalink / raw)
To: Fans of the OS Plan 9 from Bell Labs
awk(1) says, ``[s]tring constants are quoted " ", with the usual C escapes
recognized within.'', but \0 seems to terminate internal string
reprezentation...
so how do i output a real NUL byte?
--
dexen deVries
[[[↓][→]]]
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [9fans] how to output NUL byte from awk?
2013-09-17 13:47 [9fans] how to output NUL byte from awk? dexen deVries
@ 2013-09-17 14:03 ` Kurt H Maier
2013-09-17 14:36 ` dexen deVries
2013-09-17 16:50 ` erik quanstrom
2013-09-17 17:50 ` arnold
2013-09-18 7:24 ` Florian Limberger
2 siblings, 2 replies; 11+ messages in thread
From: Kurt H Maier @ 2013-09-17 14:03 UTC (permalink / raw)
To: Fans of the OS Plan 9 from Bell Labs
Quoting dexen deVries <dexen.devries@gmail.com>:
> awk(1) says, ``[s]tring constants are quoted " ", with the usual C escapes
> recognized within.'', but \0 seems to terminate internal string
> reprezentation...
>
> so how do i output a real NUL byte?
>
Does printf not do this?
khm
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [9fans] how to output NUL byte from awk?
2013-09-17 14:03 ` Kurt H Maier
@ 2013-09-17 14:36 ` dexen deVries
2013-09-17 16:50 ` erik quanstrom
1 sibling, 0 replies; 11+ messages in thread
From: dexen deVries @ 2013-09-17 14:36 UTC (permalink / raw)
To: Fans of the OS Plan 9 from Bell Labs
On Tuesday 17 of September 2013 14:03:11 Kurt H Maier wrote:
> Quoting dexen deVries <dexen.devries@gmail.com>:
> > awk(1) says, ``[s]tring constants are quoted " ", with the usual C escapes
> > recognized within.'', but \0 seems to terminate internal string
> > reprezentation...
> >
> > so how do i output a real NUL byte?
>
> Does printf not do this?
thanks
i feel really dumb now ;-)
--
dx
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [9fans] how to output NUL byte from awk?
2013-09-17 14:03 ` Kurt H Maier
2013-09-17 14:36 ` dexen deVries
@ 2013-09-17 16:50 ` erik quanstrom
2013-09-17 17:12 ` dexen deVries
` (2 more replies)
1 sibling, 3 replies; 11+ messages in thread
From: erik quanstrom @ 2013-09-17 16:50 UTC (permalink / raw)
To: 9fans
On Tue Sep 17 10:04:20 EDT 2013, khm@sciops.net wrote:
> Quoting dexen deVries <dexen.devries@gmail.com>:
>
> > awk(1) says, ``[s]tring constants are quoted " ", with the usual C escapes
> > recognized within.'', but \0 seems to terminate internal string
> > reprezentation...
> >
> > so how do i output a real NUL byte?
> >
>
> Does printf not do this?
no, awk's printf does not do that:
minooka; awk 'BEGIN{printf "%c", utf(0)}' | wc
0 0 0
minooka; awk 'BEGIN{printf "%.5s", "12\034567890"}' | xd -1
0000000 31 32 1c 35 36
minooka; awk 'BEGIN{printf "%.5s", "12\0\034567890"}' | xd -1
0000000 31 32
- erik
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [9fans] how to output NUL byte from awk?
2013-09-17 16:50 ` erik quanstrom
@ 2013-09-17 17:12 ` dexen deVries
2013-09-17 18:55 ` dexen deVries
2013-09-17 19:07 ` Kurt H Maier
2 siblings, 0 replies; 11+ messages in thread
From: dexen deVries @ 2013-09-17 17:12 UTC (permalink / raw)
To: Fans of the OS Plan 9 from Bell Labs
On Tuesday 17 of September 2013 12:50:07 erik quanstrom wrote:
> On Tue Sep 17 10:04:20 EDT 2013, khm@sciops.net wrote:
> > Quoting dexen deVries <dexen.devries@gmail.com>:
> > > awk(1) says, ``[s]tring constants are quoted " ", with the usual C
> > > escapes
> > > recognized within.'', but \0 seems to terminate internal string
> > > reprezentation...
> > >
> > > so how do i output a real NUL byte?
> >
> > Does printf not do this?
>
> no, awk's printf does not do that:
> minooka; awk 'BEGIN{printf "%c", utf(0)}' | wc
> 0 0 0
> minooka; awk 'BEGIN{printf "%.5s", "12\034567890"}' | xd -1
> 0000000 31 32 1c 35 36
> minooka; awk 'BEGIN{printf "%.5s", "12\0\034567890"}' | xd -1
> 0000000 31 32
printf "%c", 0
--
dexen deVries
[[[↓][→]]]
Take care of the luxuries and the necessities will take care of themselves.
-- L. Long
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [9fans] how to output NUL byte from awk?
2013-09-17 16:50 ` erik quanstrom
2013-09-17 17:12 ` dexen deVries
@ 2013-09-17 18:55 ` dexen deVries
2013-09-17 19:07 ` Kurt H Maier
2 siblings, 0 replies; 11+ messages in thread
From: dexen deVries @ 2013-09-17 18:55 UTC (permalink / raw)
To: Fans of the OS Plan 9 from Bell Labs
On Tuesday 17 of September 2013 12:50:07 erik quanstrom wrote:
> On Tue Sep 17 10:04:20 EDT 2013, khm@sciops.net wrote:
> > Quoting dexen deVries <dexen.devries@gmail.com>:
> > > awk(1) says, ``[s]tring constants are quoted " ", with the usual C
> > > escapes
> > > recognized within.'', but \0 seems to terminate internal string
> > > reprezentation...
> > >
> > > so how do i output a real NUL byte?
> >
> > Does printf not do this?
>
> no, awk's printf does not do that:
> minooka; awk 'BEGIN{printf "%c", utf(0)}' | wc
> 0 0 0
> minooka; awk 'BEGIN{printf "%.5s", "12\034567890"}' | xd -1
> 0000000 31 32 1c 35 36
> minooka; awk 'BEGIN{printf "%.5s", "12\0\034567890"}' | xd -1
> 0000000 31 32
utf() is the problem, %c expect int, not string:
9 awk ' BEGIN { printf "%c", 0 } ' | 9 wc
0 1 1
9 awk ' BEGIN { printf "X%cX", 0 } ' | 9 xd
0000000 58005800
--
dx
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [9fans] how to output NUL byte from awk?
2013-09-17 16:50 ` erik quanstrom
2013-09-17 17:12 ` dexen deVries
2013-09-17 18:55 ` dexen deVries
@ 2013-09-17 19:07 ` Kurt H Maier
2013-09-17 19:21 ` cinap_lenrek
2 siblings, 1 reply; 11+ messages in thread
From: Kurt H Maier @ 2013-09-17 19:07 UTC (permalink / raw)
To: Fans of the OS Plan 9 from Bell Labs
Quoting erik quanstrom <quanstro@quanstro.net>:
> On Tue Sep 17 10:04:20 EDT 2013, khm@sciops.net wrote:
>
> no, awk's printf does not do that:
> minooka; awk 'BEGIN{printf "%c", utf(0)}' | wc
not if you ask it to convert '0' to unicode and then covert
the unicode value to a char, no. I'm almost positive if you
tell it to cast 0 (the number) to char and print it, it will
give you a null byte.
khm
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [9fans] how to output NUL byte from awk?
2013-09-17 13:47 [9fans] how to output NUL byte from awk? dexen deVries
2013-09-17 14:03 ` Kurt H Maier
@ 2013-09-17 17:50 ` arnold
2013-09-18 7:24 ` Florian Limberger
2 siblings, 0 replies; 11+ messages in thread
From: arnold @ 2013-09-17 17:50 UTC (permalink / raw)
To: 9fans
dexen deVries <dexen.devries@gmail.com> wrote:
> awk(1) says, ``[s]tring constants are quoted " ", with the usual C escapes
> recognized within.'', but \0 seems to terminate internal string
> reprezentation...
>
> so how do i output a real NUL byte?
Tooting my own horn (sorry)
gawk 'BEGIN { printf("\0") }'
"No arbitrary limits" in action. :-)
Arnold
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [9fans] how to output NUL byte from awk?
2013-09-17 13:47 [9fans] how to output NUL byte from awk? dexen deVries
2013-09-17 14:03 ` Kurt H Maier
2013-09-17 17:50 ` arnold
@ 2013-09-18 7:24 ` Florian Limberger
2013-09-18 7:36 ` Bruce Ellis
2 siblings, 1 reply; 11+ messages in thread
From: Florian Limberger @ 2013-09-18 7:24 UTC (permalink / raw)
To: 9fans
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On Tue, 17 Sep 2013 15:47:17 +0200
dexen deVries <dexen.devries@gmail.com> wrote:
> awk(1) says, ``[s]tring constants are quoted " ", with the usual C
> escapes recognized within.'', but \0 seems to terminate internal
> string reprezentation...
>
> so how do i output a real NUL byte?
I know this is not very constructive and may seem like a dumb question,
but isn’t \0 the end marker for C strings? So this behaviour might be
expected?
-flo
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [9fans] how to output NUL byte from awk?
2013-09-18 7:24 ` Florian Limberger
@ 2013-09-18 7:36 ` Bruce Ellis
0 siblings, 0 replies; 11+ messages in thread
From: Bruce Ellis @ 2013-09-18 7:36 UTC (permalink / raw)
To: Fans of the OS Plan 9 from Bell Labs
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spot on. that's why:
printf "%c", 0
works, move on now.
On 18 September 2013 17:24, Florian Limberger
<flo@snakeoilproductions.net>wrote:
> On Tue, 17 Sep 2013 15:47:17 +0200
> dexen deVries <dexen.devries@gmail.com> wrote:
>
> > awk(1) says, ``[s]tring constants are quoted " ", with the usual C
> > escapes recognized within.'', but \0 seems to terminate internal
> > string reprezentation...
> >
> > so how do i output a real NUL byte?
>
> I know this is not very constructive and may seem like a dumb question,
> but isn’t \0 the end marker for C strings? So this behaviour might be
> expected?
>
>
> -flo
>
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^ permalink raw reply [flat|nested] 11+ messages in thread
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2013-09-17 13:47 [9fans] how to output NUL byte from awk? dexen deVries
2013-09-17 14:03 ` Kurt H Maier
2013-09-17 14:36 ` dexen deVries
2013-09-17 16:50 ` erik quanstrom
2013-09-17 17:12 ` dexen deVries
2013-09-17 18:55 ` dexen deVries
2013-09-17 19:07 ` Kurt H Maier
2013-09-17 19:21 ` cinap_lenrek
2013-09-17 17:50 ` arnold
2013-09-18 7:24 ` Florian Limberger
2013-09-18 7:36 ` Bruce Ellis
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