INT 61 - PCIBM PC/TCP(Transmission Control Protocol) A higher level (session layer) of the TCP/IP protocol suite. See also IP, TCP/IP. kernel v2.05+ - "enable_async" - ENABLE ASYNCHRONOUS HANDLERS AH = 12h Return: CF clear AX = previous state 0000h async calls were disabled else async calls were already enabled SeeAlso: INT 61"FTP(File Transfer Protocol) The standard protocol for copying files from one machine to another on a TCP/IP (Internet) network. Also the program of the same name with which a user may transfer files. Software",INT 61/AH=11h