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Returns the value of a simple data type specified
by a virtual address and a path. Syntax | |
symval (virtaddr pathspec)
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Formal Declaration | |
symval:any (virtaddr:ptr pathspec:str)
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Parameters | |
- virtaddr
The virtual address of the data structure. Virtaddr can be a short pointer, a long pointer, or a full
logical code pointer.
- pathspec
A path specification, as described in chapter 5, "Symbolic Formatting/Symbolic
Access."
Examples | |
$nmdebug > symopen gradtyp.demo
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Opens the symbolic data type file gradtyp.demo. It is assumed that the
Debug variable addr contains the address
of a StudentRecord data structure
in virtual memory. The following code fragment is from this file:
CONST MINGRADES = 1; MAXGRADES = 10;
MINSTUDENTS = 1; MAXSTUDENTS = 5;
TYPE
GradeRange = MINGRADES .. MAXGRADES;
GradesArray = ARRAY [ GradeRange ] OF integer;
Class = ( SENIOR, JUNIOR, SOPHOMORE, FRESHMAN );
NameStr = string[8];
StudentRecord = RECORD
Name : NameStr;
Id : Integer;
Year : Class;
NumGrades : GradeRange;
Grades : GradesArray;
END;
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$nmdebug > wl symval(addr "StudentRecord.Name")
Bill
$nmdebug > wl symval(addr, "StudentRecord.Year")
SENIOR
$nmdebug > IF symval(addr "StudentRecord.Year") = "SENIOR" THEN wl "GRAD!"
GRAD!
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Refer to the section "Using the Symbolic Formatter" in chapter 5 for more
examples including pointers, arrays, and variant/invariant record structures.
Limitations, Restrictions | |
The path specification used by the SYMVAL function must evaluate to
a simple type or a string. In particular, SYMVAL does not return
an array, a record, or a set data structure. |
