VSAM
From Just Solve the File Format Problem
VSAM (Virtual Storage Access Method) is a filesystem technology used in IBM mainframes.
VSAM is not a filesystem per se, it is a layer which sits on top of the IBM VTOC filesystem.
JCL (Job Control Language) is used to control access to such systems.
Links
- Wikipedia article
- VSAM tutorial (actually a bunch of code samples)
- Defining a Data Set with JCL
- VSAM demystified