User`s guide

SdfOpen
Syntax short SdfOpen (char far *filename);
Returns an integer(short) between 0 and 5 containing a file number. A return of 0 indicates
an error; 1 to 5 indicates a valid file.
This function attempts to open an SDF file with the indicated file name. If the file is found, the format
type of the file is read. If it is a binary SDF file, the file number is recorded in the current list of open
SDF files and returned. The returned file number may then be passed to other SDF functions to specify
the file.
Using SDF Data with C Programs
SdfOpen
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