User guide

3.1. MANIFEST CONSTANTS 39
rtn
membase, rtn memsize CIN:y, POS:y, NAT:n
These rootnode fie l ds hold, respectively, the star t of the memory block chain and
the upper bound in words of the Cintcode memory.
rtn
msecs CIN:y, POS:y, NAT:n
This field holds the number of milli-seconds since midnight. It is r e peatedly updated
by the interpreter and its value is normally cor r e ct to the nearest milli-second.
rtn
pathvar CIN:y, POS:y, NAT:n
This field holds the name of the environment variabl e givin g the direc t or i es searched
by loadseg, typically ”BCPLPATH” or ”POSPATH”. See Section 3.6 for more details.
rtn
rootvar CIN:y, POS:y, NAT: n
This field holds the name of the environment variable holding the system root
directory, typically ”BCPLROOT” or ”POSROOT”. See Section 3.6 for more details.
rtn
scriptsvar CIN:y, POS:y, NAT:n
This field holds the name of the environment variable giving the directories holding
CLI script files, typically ”BCPLSCRIPTS” or ”POSSCRIPTS”. See Section 3.6 for
more details.
rtn
screen CIN:y, POS:y, NAT:n
This rootnode field holds the stream control block for the standard screen device.
rtn
sys CIN:y, POS:y, NAT:n
Under Cintsys and Cint pos, this holds the entry point to the sys function.
rtn
tallyv CIN:y, POS:y, NAT:n
This rootnode field points to a ve c tor used to hold profile exec uti on counts. When
tallying is enabled, the value of tallyv!i is the count of how often the Cintcode
instruction at location i has been executed. The upper bound of tallyv is held in
tallyv!0. For more information about the profile facility see the stats command
described on page 125.
rtn
tasktab CIN:y, POS:y, NAT:n
Under Cintpos, this rootnode field holds the Cintpos task tabl e . The zeroth entry
is the table’s upperbound and the oth er entries are either zero or points to the task
control block (TCB) of the corresponding task. Note that the IDLE task is not held in
this table since i t is not a proper task. The IDLE task TCB is held in the rootnode’s
idletcb field.
rtn
tcblist CIN:y, POS:y, NAT:n
Under Cintpos, all TCBs are chained together in dec r eas i ng priority order. This
rootnode field points to the firs t TCB in this chain and so refers to the highest p ri or i ty
task. The last TCB on the chain has priority zero and represents the idle task.
rtn
upb CIN:y, POS:y, NAT:n
This is the upperbound of the rootnode. It value is typically 50.