HP 3000 Manuals HP 3000 Manuals
XLIBTRAP
NM and CM callable (differences noted below).
Enables or disables a user-written software library trap handling
procedure.
Syntax
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| |
| I*V I* |
| XLIBTRAP(plabel,oldplabel); |
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NOTE Any user trap handler cannot perform a GOTO out of that procedure.
Performing an ESCAPE (Pascal) or completing the trap handling
procedure are the only valid ways to return. The state of the
process and the program results are not predictable after a
non-local GOTO statement.
Parameters
plabel (NM) 32-bit signed integer by value (required)
(CM) 16-bit signed integer by value (required)
Passes the external-type label of the trap handling
procedure. If the value is 0, the trap handler is
disabled.
oldplabel (NM) 32-bit signed integer by reference (required)
(CM) 16-bit signed integer by reference (required)
Returns the plabel of the process's previous
software library trap handler. If no plabel was
previously configured, 0 is returned.
Operation Notes
When a program begins execution, the user-written software library trap
handler is disabled automatically. When enabled by the XLIBTRAP
intrinsic, and subsequently activated by an error, the user-written
software library trap handler assumes control.
This trap handler can be enabled or disabled by calling the XLIBTRAP
intrinsic.
Condition Codes
CCE (2) Request granted. Trap enabled.
CCG (0) Request granted. Trap disabled.
CCL (1) Request denied. An illegal plabel was specified.
Related Information
Intrinsics None
Commands None
Manuals Trap Handling Programmer's Guide (32650-90026)