Return the default file specification

WTSupported in traditional Synergy on Windows
WNSupported in Synergy .NET on Windows
USupported on UNIX
VSupported on OpenVMS
xcall GETDFN(file_spec[, option])



A field or record returned with the default file specification currently being used by the runtime. (a)


(optional) Determines the type of file specification that is returned: (n)

0 = Non‑ISAM file specification is returned. (default)

1 = ISAM file specification is returned.


The GETDFN subroutine returns the current default file specification being used by the runtime.

Two default file specifications are used by the runtime library, one for opening ISAM files and one for all other operations (opening non‑ISAM files; the DELET, PURGE, and RENAM external subroutines; and so forth).

On Windows and UNIX, the extension .ddf is the initial default for non‑ISAM operations and .ism is the initial default for ISAM operations.

On OpenVMS, SYS$DISK:[  ].DDF is the initial default used for non‑ISAM operations and SYS$DISK:[  ].ISM is the initial default used for ISAM operations.

The default file specification is moved to file_spec according to the rules for moving alpha data. See Moving alpha data to an alpha destination for more information.