This appendix covers the JADE external functions declared in the RootSchema jomos external function library that call Windows library functions as defined in the Microsoft Developer Network (MSDN). These external functions are declared to avoid having to declare ANSI- and Unicode-specific definitions for some commonly called Windows library functions; for example, josShellExecute calls ShellExecuteA in an ANSI environment and ShellExecuteW in a Unicode environment.
The following table maps functions defined in the RootSchema jomos external function library to the corresponding MSDN function.
| JADE External Function | Windows Function | Description |
|---|---|---|
| josCreateDirectory | CreateDirectory | Creates a directory that inherits information from other directories (security attributes default to null) |
| josDeleteDirectory | RemoveDirectory | Deletes an existing empty directory |
| josFileAccess | GetFileAttributes | Retrieves attributes for a specified file or directory (for details, see the paragraph that follows this table) |
| josFileCopy | CopyFile | Copies an existing file to a new file |
| josFileDelete | DeleteFile | Deletes an existing file |
| josGetKeyState | GetKeyState | Retrieves the status of the specified key; that is, whether the key is up, down, or toggled |
| josGetLastError | GetLastError | Retrieves the last error code value of the calling thread |
| josShellExecute | ShellExecute | Opens or prints the specified file; for example, to start another program under Microsoft Windows |
In addition to these functions, the josValidateDirectory external function is declared, which validates that the specified name is a directory.
The josFileAccess function checks the specified file to determine if it exists and whether it can be read, written, or executed. This pointer is a call for files only; if you call it with a directory name, F_FILE_NOT_FOUND is returned. (Call the josValidateDirectory function to validate a directory.) The josFileAccess parameters are:
fileName, which is a string that specifies the name of the file.
aMode, which specifies a bit pattern constructed as follows.
06, which checks for read and write permission
04, which checks for read permission
02, which checks for write permission
01, which checks for execute permission
00, which checks for the existence of the specified file
log, which specifies if invalid path exceptions are logged to jommsg.log.
The josFileAccess and josValidateDirectory calls return zero (0) if successful or they return a JADE file‑handling error in the range 5000 through 5099.
For details about:
Adding an external function to a class, see "
Browsing the RootSchema jomos external function library to obtain the JADE external function method signature, see "
External function calls, see "Using External Functions", in Chapter 1