all: check stdout and stderr status at exit

all: check stdout and stderr status at exit

If stream status is not checked at the end of execution below problem
would not report error, or non-zero exit code.  The uptime is just an
example same was true with all commands of the project.

$ uptime >&- ; echo $?
uptime: write error: Bad file descriptor
1
$ uptime >/dev/full ; echo $?
uptime: write error: No space left on device
1

Signed-off-by: Sami Kerola <kerolasa@iki.fi>