C Shared-Object File
To specify the location of a C shared-object file, you can specify the path to the dynamically-loaded executable file within a quoted pathname or as a variable.
The C shared-object filename is specified by the following
syntax:
Element | Description | Restrictions | Syntax |
---|---|---|---|
environment_var | Platform-independent indicator | Must begin with a dollar sign ( $ ) | Identifier |
pathname | Pathname to the file | See notes that follow this table | Must conform to operating system conventions |
quote | Either single ( ' ) or double ( '' ) quotation mark symbol | Opening and closing quotation mark symbols must match | Literal symbol (either ' or '') |
symbol | Entry point to the file | Must be enclosed in parentheses | Must conform to operating system conventions |
variable | Platform-independent indicator | Must begin with a dollar sign ( $ ) | Must conform to C language conventions |
The following rules affect pathname and filename
specifications in C:
- A filename (with no pathname) can specify an internal function.
- You can omit the period ( . ) symbol if pathname is relative to the current directory when the CREATE or ALTER statement is run.
- On UNIX™, an absolute pathname must begin with a slash ( / ) symbol, and each directory name must end with a slash ( / ) symbol.
- On Windows™, an absolute pathname must begin with a backslash ( \ ) symbol, and each directory name must end with a backslash ( \ ) symbol.
- The filename at the end of pathname must have the .so file extension and must refer to an executable file in a shared object library.
- Use a symbol only if the entry point to the dynamically loadable executable object file has a different name from the UDR that you are registering with CREATE FUNCTION or CREATE PROCEDURE.
- If you specify a variable, it must contain the full pathname to the executable file.
- You can include white-space characters, such as blank spaces or tab characters, within a quoted pathname.