ruby/lib/open3.rb

83 строки
1.5 KiB
Ruby

# open3.rb: Spawn a program like popen, but with stderr, too. You might also
# want to use this if you want to bypass the shell. (By passing multiple args,
# which IO#popen does not allow)
#
# Usage:
#
# require "open3"
#
# stdin, stdout, stderr = Open3.popen3('nroff -man')
#
# or:
#
# include Open3
#
# stdin, stdout, stderr = popen3('nroff -man')
#
# popen3 can also take a block which will receive stdin, stdout and stderr as
# parameters. This ensures stdin, stdout and stderr are closed once the block
# exits.
#
# Such as:
#
# Open3.popen3('nroff -man') { |stdin, stdout, stderr| ... }
module Open3
#[stdin, stdout, stderr] = popen3(command);
def popen3(*cmd)
pw = IO::pipe # pipe[0] for read, pipe[1] for write
pr = IO::pipe
pe = IO::pipe
pid = fork{
# child
fork{
# grandchild
pw[1].close
STDIN.reopen(pw[0])
pw[0].close
pr[0].close
STDOUT.reopen(pr[1])
pr[1].close
pe[0].close
STDERR.reopen(pe[1])
pe[1].close
exec(*cmd)
}
exit!(0)
}
pw[0].close
pr[1].close
pe[1].close
Process.waitpid(pid)
pi = [pw[1], pr[0], pe[0]]
pw[1].sync = true
if defined? yield
begin
return yield(*pi)
ensure
pi.each{|p| p.close unless p.closed?}
end
end
pi
end
module_function :popen3
end
if $0 == __FILE__
a = Open3.popen3("nroff -man")
Thread.start do
while line = gets
a[0].print line
end
a[0].close
end
while line = a[1].gets
print ":", line
end
end