StdioSourceAn input channel for doing blocking reads from input sources like files and sockets.
An output channel for doing blocking writes to destinations like files and sockets.
Same as In_channel.stdin
Same as Out_channel.stdout
Same as Out_channel.stderr
Same as Out_channel.printf
Same as Out_channel.print_s
Same as Out_channel.eprint_s
Same as Out_channel.eprintf
Same as Out_channel.print_string
Same as Out_channel.print_endline
Same as Out_channel.prerr_endline