DosGetSegDesc()               Get descriptor structure of segment selector.
------------------------------------------------------------------------------

 Function : Get the descriptor structure of a segment selector.

 Syntax   : USHORT BLXAPI DosGetSegDesc( SEL selector,
            PDESC segdesc);

 selector   A valid selector number whose descriptor is required.

 segdesc    Pointer to a DESC structure (see below) to receive the
            descriptor.

 Return   : Simplified segment descriptor containing the segment's base
            address, length and attributes as defined in the BLX286.H header
            file.

 This function is used to obtain all the information about a particular
 selector.

 Example:

    #include <stdlib.h>
    #include <stdio.h>
    #include <string.h>
    #include <blx286.h>
    void main (void)
    {
    DESC        segdesc;
    if (DosGetSegDesc(SELECTOROF(main),&segdesc) == 0)
       {
       printf ("Current code segment base address is %08Xh\n",
          segdesc.segbase);
       printf ("Current code segment length is %08Xh\n",
          segdesc.seglen);
       printf ("Current code segment attributes are %04Xh\n",
          segdesc.segattrib);
       }
    }