Intel XENIX 286 Programmers Guide (86) - Tenox.tc

adb: Program Debugger XENIX Programming
Changing the Memory Map
You can change the values of a memory map by using the ?m and /m commands. These
commands assign specified values to the corresponding map entries. The commands
have the form
and
?m segment-number file-position size
/m segment-number file-position size
where segment-number gives the number of the segment map you wish to change, fileposition
gives the offset in the file to the beginning of the given address, and size gives
the segment size in bytes. ?m assigns values to a text segment entry and /m to a data
segment entry.
For example, the following command changes the file position for segment 63 in the
text map to Ox2000:
?m 63 Ox2000
The command
/m 39 OxO
changes the file position for segment 39 in the data map to 0.
Creating New Map Entries
You can create new segment maps and add them to your memory map by using the ?M
and /M commands. Unlike ?m and /m, these commands create a new map instead of
changing an existing one. These commands have the form
and
?M segment-number file-position size
/M segment-number file-position size
where segment-number gives the number of the segment map you wish to create, fileposition
gives the offset in the file to the beginning of the given address, and size gives
the segment size in bytes. ?M creates a text segment entry and /M creates a data
segment entry. The segment number must be unique. You cannot create a new map
entry that has the same number as an existing one.
The ?M and /M commands are especially useful if you wish to access segments otherwise
allocated to your program. For example, the command
?M 71 0 2504
creates a text segment entry for segment 71 with size 2504 bytes.
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