Status words

One set of status words per unit will be kept in a common block (which should reside in the root for overlayed programs). The status words contain all information the routines have to know in order to operate. The shorthand notations 'physical header' and 'record header' refer to the physical and logical headers respectively of the EP format description.

Words marked '*' can be defined and changed by the user through calls to special routines (the user should not write into the status word area directly).

r, w, and r/w under 'use' means reading or writing only, or both.

: Overview of the status words

The status words are kept in a common block

      COMMON/EPCOMM/NMUNIT,NWUNIT,NCONT,ISTART,LASTUT,LREF,LIST($dim)

with

NMUNIT

max. no. of units supported simultaneously, reading plus writing (default = 10).

NWUNIT

number of status words per unit according to list above (default = 32).

NCONT

number of overall control words for package according to list below (default = 8).

ISTART

internal reference flag

LASTUT

internal reference flag

LREF

internal reference flag

LIST

status word list, with $dim = NCONT+NWUNIT*NMUNIT, this allows the support of more units than the default 10 (see below) default value of $dim = 350.

• Important note