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IBM Mainframe Kermit

Kermit-370 is a family of programs implementing the Kermit file transfer protocol for IBM 370-series mainframes (System/370, 303x, 43xx, 308x, 3090, System/390, etc.) under a variety of operating systems. Kermit-370 operates:

It can also be used to transfer files over incoming TELNET (linemode) or TN3270 (fullscreen) connections.

Kermit-370 is written in IBM 370 assembly language and is compatible with the F, VS, and H assemblers. The Kermit protocol implementation is among the most advanced available, lacking only sliding windows due the half-duplex nature of IBM mainframe communications, but including a vast array character-set translations.

Kermit-370 4.3.2 for IBM Mainframes with VM/CMS, MVS/TSO, OS/390, CICS, or MUSIC was released on 16 December 1997. Its major new features are:

IBM Mainframe Kermit may be downloaded from the Columbia Kermit software archive kermit/b directory:

For VM/CMS
Files ik0*.* and ikc*.*.
Manual: ikcker.txt (plain text), ikcker.ps (PostScript), ikcker.pdf (PDF).
For MVS/TSO (including ROSCO) or OS/390
Files ik0*.* and ikt*.* (add ikr*.* for ROSCOE).
Manual: iktker.txt (plain text), iktker.ps (PostScript), iktker.pdf (PDF).
For CICS
Files ik0*.* and ikx*.*.
Manual: ikxker.txt (plain text), ikxker.ps (PostScript), ikxker.pdf (PDF).
For MUSIC
Files ik0*.* and ikm*.*.
Manual: ikmker.txt (plain text), ikmker.ps (PostScript), ikmker.pdf (PDF).

For further information see the following plain ASCII files:

The 4.3.2 upgrade is in the form of "update" (.upd) files kept with the regular files. Apply them as updates to your current version (4.3.0 or later) by replacing your current update files with the new ones and rebuilding:


IBM Mainframe Kermit / Columbia University / [email protected] / 12 Feb 1999
Updated 7 Jan 2006 (PDF versions of manual chapters) / 15 Sep 2010 (format)
Updated 1 August 2021 (FTP links changed to HTTP)