Handle unusual errors during process spawning
Handle unusual errors during process spawning

Only print "Command not found: ...", if the error is actually that the command
is not found. Otherwise print a general error description from the system. I
found that while trying to echo to the example scheme (:vec) I was getting
EBADF which caused "command not found: /bin/ion" to be printed.

jwbowen/ion,bheesham/ion,redox-os/ion,redox-os/ion,redox-os/ion,jwbowen/ion,bheesham/ion