* Revert "Revert "Try again: in unix like system, set foreground process while running external command (#6273)" (#6542)"
This reverts commit 2bb367f570.
* Make foreground job control hopefully work correctly
These changes are mostly inspired by the glibc manual.
* Fix typo in external command description
* Only restore tty control to shell when no fg procs are left; reuse pgrp
* Rework terminal acquirement code to be like fish
Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
* Revert "Fix intermittent test crash (#6268)"
This reverts commit 555d9ee763.
* make a working version again
* try second impl
* add
* fmt
* check stdin is atty before acquire stdin
* add libc
* clean comment
* fix typo
* while executing external command, make it as foreground
* remove useless file
* add comment, make var more readable
* add comment
* fmt code
* fix windows
* fix func name
* fix clippy
* fix windows clippy
* add comments, introduce `ForegroundProcess and ForegroundChild
* fix windows clippy
* fix on windows
* no need fg_process_setup module
* Revert "no need fg_process_setup module"
This reverts commit 21ee4ffbf6.
* restrict visibility for helper functions
