User`s guide

SdfScanVar
Syntax int SdfScanVar (short fn, short varInx, struct SDF_SCAN_VAR far *scanVar);
Returns an integer (short) of zero or minus one. A return of 0 indicates no error; a return of
−1indicatesanerror.
This function reads the scan variable information from an open SDF file, where fn is the number of the
open SDF file (for details, see SdfOpen). The information is put in the SDF_SCAN_VAR structure,
where scanVar is the pointer to the structure.
The varInx parameter selects the scan variable that you want to examine. The first variable (varInx equal
to zero) is actually an SDF_SCAN_VAR record created from the SDF_SCAN_STRUCT record in the
SDF file. Most instruments don’t have true SDF_SCAN_VAR records, but do have the
SDF_SCAN_STRUCT record, so you will usually specify 0 (zero) for this parameter. The HP 89410A
and HP 89440A do use 3 addition scan variable records for waterfall data, so you may specify a varInx
from 0 to 3.
Using SDF Data with C Programs
SdfScanVar
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