CALL Function (LibreOffice Calc)

• Calls a function inside a native shared library
• Passes arguments directly to compiled code
• Returns the result to the spreadsheet
• Supports multiple parameter types
• Requires macro security settings to allow external code execution

Basic form

CALL(module; function; return_type; arg1; arg2; ...)

Arguments

• module:
  Path or name of the shared library (DLL or .so).

• function:
  Name of the exported function to call.

• return_type:
  A string specifying the return type (e.g., “I”, “D”, “C”, “P”).

• arg1, arg2, … (optional):
  Arguments to pass to the external function.

Call a DLL function (Windows)

=CALL("mylib.dll"; "AddNumbers"; "I"; 5; 7)

Call a shared library (Linux)

=CALL("/usr/lib/libmath.so"; "cos"; "D"; 1.0)

Call a void function

=CALL("logger.dll"; "LogEvent"; "V"; "Started")

Using REGISTER.ID to simplify repeated calls

=REGISTER.ID("mylib.dll"; "Multiply"; "DII")
→ returns a function ID

Then:

=CALL(A1; 3; 4)

Passing strings to native code

=CALL("textlib.dll"; "Process"; "C"; "Hello")

Calling a function that returns a pointer

=CALL("sys.dll"; "GetHandle"; "P")

Using CALL inside a larger formula

=IF(A1>0; CALL("calc.dll"; "Compute"; "D"; A1); 0)

CALL is disabled by default

You must enable:

• Tools → Options → LibreOffice → Security → Macro Security
• Allow “Execute external code” (varies by version)

Behavior details

• If the library cannot be loaded → Err:504
• If the function cannot be found → Err:508
• If parameter types mismatch → Err:502
• If the function crashes → LibreOffice may crash

Platform differences

• Windows uses .dll
• Linux uses .so
• macOS support is limited

Err:504 — Module not found

Fix:

• Check library path
• Ensure correct file extension

Err:508 — Function not found

Fix:

• Verify exported symbol name
• Check case sensitivity

Err:502 — Invalid argument

Fix:

• Ensure correct type codes
• Validate argument count

• Use CALL only when absolutely necessary
• Prefer UNO API or macros for modern integrations
• Keep DLLs in trusted locations
• Document parameter types clearly
• Disable CALL in shared environments

• REGISTER.ID — register external functions
• DDE — dynamic data exchange
• HYPERLINK — open external resources
• INDIRECT — dynamic references
• UNO macros — modern automation

By understanding CALL, you can integrate LibreOffice Calc with native code, but always with caution and strict security controls.