Feature: spin until a file descriptor changes.

[x85446]

I want to spin until a file descriptor changes.

I have already implemented it, but want to see if you guys want any changes to how you call it.

Option A (as implemented):

• ignore the command section
• pass a flag with string
  gum spin --file-change=/tmp/c1 " -- ""

current help

Usage: gum spin <command> ... [flags]
...
  -f, --file-change=STRING    Spin until file descriptor changes. (Command not run.)

Option B:

take over the command section with the path
gum spin --file-change " -- "/path/to/file"

possible help

Usage: gum spin <command | path> ... [flags]
...
  -f, --file-change   Spin until file descriptor changes. (Provide path as arg.)

Option C

workaround: install fswatch and call it
gum spin -- fswatch -1 /tmp/c1