This
topic outlines the use of Virtual Storage Access
Method (VSAM) data sets in
z/OS® XL C/C++. Three
I/O processing modes for VSAM data sets are available in
z/OS XL C/C++:
- Record
- Text Stream
- Binary Stream
Because VSAM is a record-based access method, record mode is the
logical processing mode and is specified by coding the type=record keyword
parameter on the fopen() function
call. z/OS XL C/C++ also
provides limited support for VSAM text streams and binary streams.
Because of the record-based nature of VSAM, this topic is organized differently from the other topics in this section. The focus of this topic is on record I/O, and only those aspects
of text and binary I/O that are specific to VSAM are also discussed.
See
z/OS XL C Support for the double-byte character set for information about
using wide-character I/O with
z/OS XL C/C++.
Notes: - This topic describes C I/O as it can be used within C++ programs.
- The C++ I/O
stream libraries cannot be used for VSAM I/O because these do not
support the record processing mode (where type=record is
specified).
- Starting in z/OS V1R10, the C/C++ runtime library provides support
for VSAM data sets in the extended addressing space on extended address
volumes (EAVs).