Users and shared memory.

Shared user particulars.

Since Megistos is a distributed system, no central authority keeps state. Each process is individually responsible for the user running it.

However, every now and then transactions between users will have to be performed (that is ultimately the point of being of any BBS --- interaction and communication between users, the underlying BBS system should try to be as transparent as possible).

Thus, the BBS Daemon allocates one 4 kbyte System V IPC shared memory segment for each user. Each process ran by the user automatically has this segment attached, but it is also able to attach the segments of other users, so as to effect transactions between them. The current user is referred to by the highly technical term `this user'. The optional additional user is known as `other user'. You can use certain functions within this part of the BBS API to attach other users' segments to your `other user' pointer. `This user' pointer is always and immutably set to the user owning the current process.

shmuserrec

Per-user shared memory segment.

thisuseracc

This user's account.

othruseracc

Other user's account.

thisuseronl

This user's online record.

othruseronl

Other user's online record.

_thisuseraux

This user's shared scratch space.

_othruseraux

Other user's shared scratch space.

See Also:

thisuseracc, othruseracc, thisuseronl, othruseronl, _thisuseraux, _othruseraux.

Alphabetic index