OS_EvaluateExpression
OS SWI Calls
» OS_EvaluateExpression
OS_EvaluateExpression
(SWI &2D)
| Entry | |
|---|---|
| R0 | Pointer to string |
| R1 | Pointer to buffer |
| R2 | Length of buffer |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | 0 if integer returned, else preserved |
| R2 | Integer if R1=0, else length of string |
Use
The purpose of this call is to evaluate a string and return the value into a given buffer as either a string or integer.
Notes
This SWI takes a string, evaluates it, and places result in given buffer. Type of the result is given in R1 :
| 0 | Integer returned in R2 |
| Not 0 | Pointer to string, length in R2 |
For a comprehensive list of expressions that can be used with this SWI please see the Expressions page.
Floating point numbers cannot be used within expressions.
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