Description

This routine is used when some initial system information is required before the BLACS are set up. On all platforms except PVM,

nprocs

is the actual number of processes available for use, that is,

nprows

*

npcols

<=

nprocs

. In PVM, the virtual machine may not have been set up before this call, and therefore no parallel machine exists. In this case,

nprocs

is returned as less than one. If a process has been spawned via the keyboard, it receives

mypnum

of 0, and all other processes get

mypnum

of -1. As a result, the user can distinguish between processes. Only after the virtual machine has been set up via a call to

BLACS_SETUP

, this routine returns the correct values for

mypnum

and

nprocs

.