HP 3000 Manuals HP 3000 Manuals
func cst
Coerces an expression into a CST absolute code pointer (ACPTR).
Syntax
cst (value)
CM program segments are loaded into the CSTX. CM library segments are
loaded into the CST.
During the evaluation of the parameter to the CST function, the following
CM search path is used for procedure name lookups:
GRP, PUB, LGRP, LPUB, SYS
Formal Declaration
cst:cst (value:any)
Parameters
value An expression to be coerced. All types are valid.
Derivation of the CST Bit Pattern
--------------------------------------------------------------------------------------------
| | |
| Parameter Type | Action |
| | |
--------------------------------------------------------------------------------------------
| | |
| BOOL | 0.1 if TRUE, 0.0 if FALSE. |
| | |
--------------------------------------------------------------------------------------------
| | |
| U16 | Set the high-order 32 bits (SID or segment part) to zero. |
| S16 | Right justify the original 16-bit value in the low-order 32 |
| | bits (offset part) with zero fill. |
| | |
--------------------------------------------------------------------------------------------
| | |
| U32 | Set the high-order 32 bits (SID or segment part) to zero. |
| S32 | Transfer the original bit pattern into the low-order 32 bits |
| SPTR | (offset part) unchanged. |
| | |
--------------------------------------------------------------------------------------------
| | |
| LPTR SYS | Transfer both parts of the address unchanged. |
| PROG USER | |
| GRP TRANS | |
| PUB CST | |
| LGRP CSTX | |
| LPUB | |
| | |
--------------------------------------------------------------------------------------------
| | |
| STR | Transfer the ASCII bit pattern for the last eight characters |
| | in the string. Strings shorter than eight characters are |
| | treated as if they were extended on the left with nulls. |
| | |
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Examples
%cmdebug > wl cst(12.304)
CST %12.304
Coerce the simple long pointer into a CST absolute code pointer.
%cmdebug > wl sort
PROG %4.3302
%cmdebug > wl grp (sort)
GRP %2.1364
%cmdebug > wl cst (sort)
CST %73.1364
Print the address of the procedure named sort. The first lookup uses the
standard procedure name lookup search path and finds the procedure sort
in the program file. The second lookup restricts the search path to the
group library, and another sort procedure is located. The third lookup
restricts the search path to all of the currently loaded libraries, and
the second procedure is located again (within the group library).
%cmdebug > wl cst(sys(24.630))
CST %24.630
The coercion simply changes the associated absolute file. Note that no
complicated conversion or range checking is performed.
Limitations, Restrictions
none