Object Table

The number of entries in the Object Table is given by the # Objects in Module field in the linear EXE header. Entries in the Object Table are numbered starting from one. Each Object Table entry has the following format

          ﾚﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾂﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄｿ
      00h ｳ     VIRTUAL SIZE      ｳ    RELOC BASE ADDR    ｳ
          ﾃﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾅﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄｴ
      08h ｳ     OBJECT FLAGS      ｳ    PAGE TABLE INDEX   ｳ
          ﾃﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾅﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄｴ
      10h ｳ  # PAGE TABLE ENTRIES ｳ       RESERVED        ｳ
          ﾀﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾁﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾄﾙ

Object Table

VIRTUAL SIZE = DD Virtual memory size. This is the size of the object that will be allocated when the object is loaded. The object data length must be less than or equal to the total size of the pages in the EXE file for the object. This memory size must also be large enough to contain all of the iterated data and uninitialized data in the EXE file.

RELOC BASE ADDR = DD Relocation Base Address. The relocation base address the object is currently relocated to. If the internal relocation fixups for the module have been removed, this is the address the object will be allocated at by the loader.

OBJECT FLAGS = DW Flag bits for the object. The object flag bits have the following definitions.

0001h = Readable Object.
0002h = Writable Object.
0004h = Executable Object. The readable, writable and executable flags provide support for all possible protections. In systems where all of these protections are not supported, the loader will be responsible for making the appropriate protection match for the system.

0008h = Resource Object.
0010h = Discardable Object.
0020h = Object is Shared.
0040h = Object has Preload Pages.
0080h = Object has Invalid Pages.
0100h = Object has Zero Filled Pages.
0200h = Object is Resident (valid for VDDs, PDDs only).
0300h = Object is Resident Contiguous (VDDs, PDDs only).
0400h = Object is Resident 'long-lockable' (VDDs, PDDs only).
0800h = Reserved for system use.
1000h = 16
2000h = Big/Default Bit Setting (80x86 Specific). The 'big/default' bit , for data segments, controls the setting of the Big bit in the segment descriptor. (The Big bit, or B-bit, determines whether ESP or SP is used as the stack pointer.) For code segments, this bit controls the setting of the Default bit in the segment descriptor. (The Default bit, or D-bit, determines whether the default word size is 32-bits or 16-bits. It also affects the interpretation of the instruction stream.)

4000h = Object is conforming for code (80x86 Specific).
8000h = Object I/O privilege level (80x86 Specific). Only used for 16

PAGE TABLE INDEX = DD Object Page Table Index. This specifies the number of the first object page table entry for this object. The object page table specifies where in the EXE file a page can be found for a given object and specifies per-page attributes. The object table entries are ordered by logical page in the object table. In other words the object table entries are sorted based on the object page table index value.

PAGE TABLE ENTRIES = DD # of object page table entries for this object. Any logical pages at the end of an object that do not have an entry in the object page table associated with them are handled as zero filled or invalid pages by the loader. When the last logical pages of an object are not specified with an object page table entry, they are treated as either zero filled pages or invalid pages based on the last entry in the object page table for that object. If the last entry was neither a zero filled or invalid page, then the additional pages are treated as zero filled pages.

RESERVED = DD Reserved for future use. Must be set to zero.

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