Calling DLL Passing arguments to DLL functions
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User's Guide
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Passing arguments to DLL functions
Passing arguments to DLL functions
This section discusses:
·
The valid data types for arguments passed to DLL functions
·
How to pass string arguments
·
How to pass arguments to functions that expect pointers
·
How to pass arguments that can be modified by the DLL function
·
How to pass window handles to a DLL function
Data types of
arguments
Since DLL functions are written in C, the arguments you pass to these
functions must have the appropriate C data types. In addition to the standard
4Test data types, SilkTest also supports these ten C data types:
·
char, int, short, and long
·
unsigned char, unsigned int, unsigned short, and unsigned long
·
float and double
Any argument you pass must have one of these data types (or be a record that
contains fields of these types).
Strings
The char* data type in C is represented by the 4Test
STRING
data type. The
default string size is 256 bytes.
The following code fragments show how a char array declared in a C struct is
declared as a
STRING
variable in a 4Test record:
// C declaration
typedef struct
{
...
char szName[32];
...
}
mswutil.inc
Contains the following utility functions:
· PrintMemManInfo
· PrintTaskList
· PrintWindowDetail
· GetStyleBitList
· PrintStyleBits
Include file
Description
