When the bar is getting input from a loop with a pause, there
can be a noticable delay to visually updating the bar on click
events. By letting bar call an input command it can now update
instantly on a click event and still have a delay so it's not
an idle hog.
Something like:
while true; do date; sleep 10; done | bar -d
Now becomes:
bar -d -c "date" -t 10
Either option may be ommited and the bar will still perform as
before. If a command (-c) is given but not a timeout (-t) then
the timeout defaults to 5 seconds.
Changed compiler standard to gnu99 for use with popen()/pclose()
-Os provides -O2 minus some optimizations that would
increase size, plus optimizations that would decreaze
size, plus -Os usually takes caching into account.
-Os Optimize for size. -Os enables all -O2 optimizations that do not
typically increase code size. It also performs further optimizations
designed to reduce code size.
