GNU bug report logs - #33281
head does not consume input after '-c' is satisfied

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Luiz Angelo Daros de Luca <luizluca <at> gmail.com>
To: bug-coreutils <at> gnu.org
Subject: head does not consume input after '-c' is satisfied
Date: Mon, 5 Nov 2018 18:30:17 -0200

[Message part 1 (text/plain, inline)]

Hello,

Once head read enough bytes to satisfy -c option, it stops reading input
and quit.
This is different from what -n does and it is also different from both
FreeBSD and busybox head implementation.

With GNU Coreutils head:

$ echo -e "123\n456\n789" | { head -n 1; while read a; do echo "-$a-";
done; }
123
$ echo -e "123\n456\n789" | { head -c 4; while read a; do echo "-$a-";
done; }
123
-456-
-789-
$

With all other head implementations I tested:

$ echo -e "123\n456\n789" | { head -c 4 ; while read a ; do echo "-$a-" ;
done ; }
123
$

It would make sense to both -n and -c have the same meaning, differing only
whether to read bytes or lines.

Regards,
-- 

Luiz Angelo Daros de Luca
luizluca <at> gmail.com

[Message part 2 (text/html, inline)]

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