[Overview][Constants][Types][Procedures and functions][Variables][Index] | Reference for unit 'go32' (#rtl)

# segment_to_descriptor

Map segment address to descriptor

## Declaration

Source position: go32.pp line 90

`function segment_to_descriptor(`
`seg: Word`
`):Word;`

## Description

Maps a real mode segment (paragraph) address onto an descriptor that can be used by a protected mode program to access the same memory.

Parameters:

seg
  the real mode segment you want the descriptor to.

Return values: Descriptor to real mode segment address.

Remark: | The returned descriptors limit will be set to 64 kB. Multiple calls to this function with the same segment address will return the same selector. Descriptors created by this function can never be modified or freed. Programs which need to examine various real mode addresses using the same selector should use the function allocate_ldt_descriptors and change the base address as necessary.

For an example, see seg_fillchar.

## Errors

Check the int31error variable.

## See also

allocate_ldt_descriptors |  | Allocate a number of descriptors
free_ldt_descriptor |  | Free a descriptor
set_segment_base_address |  | Set descriptor's base address