fold: does not handle broken pipe in the same way as GNU

[ngtv2409]

Component

fold

Description

GNU fold lets the kernel kill the pipeline cleanly without any extra handling steps while UU fold handles the broken pipe, prints fold: broken pipe and exit with code 1.

Reproduction

To simulate a broken pipe, we can use this command
yes a | fold -w1 | head -n1. yes a creates an infinite stream of as for fold -w1 whose output is piped to head -n1, which terminate after the first line of output, thus create a broken pipe where reader is terminated unexpectedly.

Using the GNU implementation, nothing happens beside code 141 when bash set -o pipefail.

$ yes a | fold -w1 | head -n1
a
$ echo $?
141

$ yes a | uu fold -w1 | head -n1
a
fold: Broken pipe
$ echo $?
1

Impact

A behavioral difference to GNU coreutils

Note

The handling of errors seem to be located in uucore::error meaning this issue may affect many other utilities.

[ChrisDryden]

Same root cause as this: #10260 just need to add the pipe signal handlers