[xtf]

my simple jobqueue, if I need one

  waitfor() {
    while pgrep $1 >/dev/null; do sleep 2; done && $*
  }

[unhammer]

If I may provide some feedback:

    Line 2:
        while pgrep $1 >/dev/null; do sleep 2; done && $*
                    ^-- SC2086: Double quote to prevent globbing and word splitting.
                                                       ^-- SC2048: Use "$@" (with quotes) to prevent whitespace problems.

Also, how do you pick the right job to wait for if several programs match $1? (E.g. if it's a bash script, $1 will be "bash", which on my system matches lots of things.)

Also, a 2s sleep will slow things down if you want to use it for a whole lot of jobs.

Also, this won't run your second command if the first command you wait for has already exited!

Also, shouldn't $* be `shift; "$@"` or do you only ever queue jobs of the same command?

[xtf]

Just a simple one when needed. cp, downloader, etc. Nothing too complicated.