Calling external functions on UNIX
In PowerBuilder custom class user objects that you plan to
deploy as EAServer components
on a UNIX platform, you can call external functions in shared libraries
compiled on the operating system where the server is running. You cannot
call external functions in libraries that make Windows API calls
or rely on graphical processing.
You use the standard PowerScript syntax to declare functions
that reside in UNIX shared libraries. For example, this statement
declares the function getcwd in the standard
C library on Solaris:
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FUNCTION string getcwd(REF string buff, & |
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unsigned int size) LIBRARY "/usr/lib/libc.so" |
You call the function from a script in your application in
the way you call any other function. In this example, the space function
allocates enough space to hold the directory name returned by getcwd:
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string ls_return, ls_directory |
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ls_directory = space(100) |
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. . . |
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ls_return = getcwd(ls_directory, 100) |
Updating the load library path
On UNIX, when your component calls an external function, it
must be able to find the shared library in which that function resides.
To ensure this, you must update the library path environment variable
to include the directory where that shared library is stored.