stty should accept $(stty -a) as its arguments

[gnachman]

A common pattern to save and restore terminal state is:

SAVED=$(stty -g)
…do stuff that changes terminal state…
stty "$SAVED"

However, uu's stty cannot parse its own -g output.

bash-5.1$ /opt/homebrew/Cellar/uutils-coreutils/0.3.0/bin/ustty -g
6b02:3:4b00:200005cf:4:ff:ff:7f:17:15:12:0:3:1c:1a:19:0:0:16:f:1:0:14:0
bash-5.1$ /opt/homebrew/Cellar/uutils-coreutils/0.3.0/bin/ustty $(/opt/homebrew/Cellar/uutils-coreutils/0.3.0/bin/ustty -g)
ustty: invalid argument '6b02:3:4b00:200005cf:4:ff:ff:7f:17:15:12:0:3:1c:1a:19:0:0:16:f:1:0:14:0'

[3v1n0]

Duplicate of #8608

[ChrisDryden]

This merged PR should close the issue: #9480

There are integration tests on most platforms for the stty $( stty -g ) commands that matches whats in the GNU test suite but there is still some unfinished work that the output of stty -g does not match the GNU implementation on all platforms

[ChrisDryden]

It appears that the mismatch in stty -g was caused by incorrect fallback patterns and using stdout instead of stdin as the fallback #8608 (comment) once that associated PR is in all of the outstanding issues associated with stty -g can be closed

[ChrisDryden]

This issue should be fully fixed now that #9881 is merged