User guide

3.1. MANIFEST CONSTANTS 35
function name is too long its first and last five character are packed into the string
separated by a single quote ’. Typically entryword=#x0000DFDF.
fl
. . . CIN:y, POS:y, NAT:n
Constants of the form fl
... are mnemonics for the floating point operations
performed by the call sys(Sys
flt, op, ...) as described near page 65.
globword CIN:y, POS:y, NAT:n
This constant is used to assist the debugging of Cintcode programs. If the i
th
global
variable is not otherwise set, its value is globword+i. Typically globword=#x8F8F0000.
id inscb, id inoutscb, id outscb CIN:y, POS:y, NAT:n
These constants are mnemonics for the possible values of the id field of a stream
control block. See scb
id below.
InitObj CIN:y, POS:y, NAT:y
This ident i fie s the position of the init method in objects using BCPL’s version of
object oriented programming. Typical use is as follows:
InitObj#(obj, arg1, arg2)
For more details, see mkobj described on page 55.
isrregs CIN:n, POS:y, NAT:n
Under Cintpos this is the location in Cintcod e memory used to hold the Cintcode
registers representing the state at the start of the interrupt service routine.
klibregs CIN:n, POS:y, NAT:n
Under Cintpos This is the location in Cintcode memory used to hold Cintcode
registers during system star tu p.
mcaddrinc CIN:y, POS:y, NAT:y
This is the difference between machine addre sse s of consec ut i ve words in memory
and is usually 4 or 8. Very occasionally, BCPL implementions have negatively growing
stacks, in which case mcaddrinc will be negative.
maxint, minint CIN:y, POS:y, NAT:y
The constant minint is 1<<(bitsperword-1) and maxint is =minint-1. They hold
the most negative and largest positive numbers that can be represented by a BCPL
word. On 32-bit implementations, they are normally #x80000000 and #x7FFFFFFF.
pollingch CIN:n, POS:y, NAT:n
This is the value returned by rdch if a charcter is not immediately available from
the currently selected stream. Its value is normally -3. Curre ntly only TCP streams
under Cintpos provide the polling mechanism.
rootnodeaddr CIN:y, POS:y, NAT:n
This manifest constant is used in Cintsys and Cintpos to hold the ad dr es s of the
root node. It s value is otherwis e zero.