Bash – change the shell’s wildcards

I don't think any shell does anything beyond whitespace munging when storing commands into the history. What * expanded to is not recorded, and there doesn't seem to be an option to record it.

Note that it would not be possible to record in full generality anyway. For example, if you run a='foo* bar*'; rm $a (rm $=~a in zsh), the shell is unlikely to detect the wildcard match syntactically. And there's no option to log all glob expansions.

You could cobble something together with preexec (or the bash equivalent). Untested first go (for zsh):

history_wildcards=()
precmd () {
  emulate -LR zsh
  local n tmp
  history -1 | read n tmp
  history_wildcards[$(($n+1))]=$=~1
}

This fills the history_wildcards array to a string with the glob expansion of each word in the command line. Word splitting is performed in the naive way, so something like echo ' /**/* ' will expand /**/* (i.e. traverse your disk). Don't expect anything useful from cd subdir && echo * or anything so mind-bogglingly nontrivial.

If you plan beforehand, you can make zsh expand the wildcards before you submit the command. In the default configuration, just press Tab when your cursor is on the glob. If you've configured completion differently, try ^X * (expand-word).

I agree with your analysis and I agree it sounds like you have to detect whether your process group is orphaned or not.

tcsetattr is also meant to return EIO if the process group is orphaned (and we're not blocking/ignoring SIGTTOU. That might be a less intrusive way than a read on the terminal.

Note that you can reproduce it with:

(bash<&1 &)

You need the redirection otherwise stdin is redirected to /dev/null when running a command in the background.

(bash<&1 & sleep 2)

Gives even weirder behaviour, as because you end up with two shells reading from the terminal. They are ignoring SIGTTIN and the new one is not detecting, once it's started that it is no longer in the foreground process group.

ksh93's solution is not so bad: only go up to 20 times (instead of infinite) through that loop before giving up.