Replace the running program by starting Command. Command is a
callable term. The functor is the command and the arguments
provide the command-line arguments for the command. Each
command-line argument must be atomic and is converted to a
string before passed to the Unix call execvp(). Here are some
examples:
exec(ls('-l'))exec('/bin/ls'('-l', '/home/jan'))
Unix exec() is the only way to start an executable file
executing. It is commonly used together with fork/1. For example
to start netscape on an URL in the background, do:
run_netscape(URL) :-
( fork(child),
exec(netscape(URL))
; true
).
Using this code, netscape remains part of the process-group of
the invoking Prolog process and Prolog does not wait for
netscape to terminate. The predicate wait/2 allows waiting for a
child, while detach_IO/0 disconnects the child as a deamon
process.
