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Certain MFS codes do not have a corresponding BASIC+ or System Monitor command to call them. Examples include RECORD.COUNT and INSTALL.

If a program requires access to these codes, it must execute a direct call to the first MFS for the file to be accessed. This is done as an external subroutine call to the first MFS for the file, passing the seven filing system arguments.

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The handle returned by the BASIC+ OPEN statement also contains the MFS list for a file. In this situation, the MFS list is the first value (delimited with @VM) in the handle, and the true file handle is the second value. The MFS list returned as part of the BASIC+ OPEN file handle is already @SVM-delimited, so no conversion is required.

The following sample program illustrates how to execute a direct call to the first MFS for a file. The example program calls the filing system with a code of 28 (RECORD.COUNT) to return the total number of records in the file.

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