Posted to tcl by pooryorick at Fri Aug 03 06:13:38 GMT 2018view pretty

set chan [open |[list [info nameofexecutable] - 2>@stderr] r+]
puts $chan {
	while {[gets stdin var]} {
			puts stderr [list yyy $var]
		}
	}
puts $chan xxx
close $chan write
set res [read $chan]
puts $res