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Re: echo $'\0' >a does not write the nul byte
From: |
Chet Ramey |
Subject: |
Re: echo $'\0' >a does not write the nul byte |
Date: |
Sun, 17 Jan 2021 16:02:51 -0500 |
User-agent: |
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 |
On 1/17/21 3:05 PM, hans@artax.karlin.mff.cuni.cz wrote:
Description:
Command
echo $'\0' |od -c
writes
0000000 \n
0000001
in contrast to
echo $'\1' |od -c
0000000 001 \n
0000002
The nul byte is not echoed by $'\0'.
Repeat-By:
echo $'\0' |od -c
echo $'\1' |od -c
Shell builtin commands obey the same argv conventions as any other Unix
program: arguments are null-terminated strings. That means that
echo $'\0'
echo ''
echo ""
are all equivalent, and none of them will output a null byte.
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/