LIBRARY function

Parses a character string in the form path-name<<member-name>>, where path-name is the pathname of an ABL r-code library and member-name is the name of a file within the library, and returns the pathname of the library. The double angle brackets indicate that member-name is a file in a library. If the string is not in this form, the LIBRARY function returns the Unknown value (?).

Typically, you use the LIBRARY function with the SEARCH function to retrieve the name of a library. The SEARCH function returns character strings of the form path-name<<member-name>> if it finds a file in a library.

Syntax 

 

LIBRARY ( string )

string

A character expression whose value is the pathname of a file in a library. In Windows, the pahtname cannot contain characters outside of the non-Unicode code page. See OpenEdge Development: Internationalizing Applications for more information about Unicode and code pages.

Example 

This procedure searches for a file that you specify. It displays a message indicating whether the file is not found in your path, is found in a library within your path, or is found in your path but not in a library.

 

r-rlib.p

DEFINE VARIABLE what-lib AS CHARACTER NO-UNDO. DEFINE VARIABLE location AS CHARACTER NO-UNDO. DEFINE VARIABLE myfile AS CHARACTER NO-UNDO FORMAT "x(16)"   LABEL "R-code File".   SET myfile. location = SEARCH(myfile).   IF location = ?THEN DO:   MESSAGE "Can’t find" myfile.   LEAVE. END.   what-lib = LIBRARY(location). IF what-lib <> ? THEN   MESSAGE myfile "can be found in library" what-lib. ELSE   MESSAGE myfile "is not in a library but is in" location.

Note 

You can improve the performance of an application by using the SEARCH and LIBRARY functions for any files you want to execute that you specify with a relative pathname. For example, if you want to execute a procedure file several times that you specify with a relative pathname, you can return the absolute pathname for the file using the SEARCH and LIBRARY functions, then execute the RUN statement with that absolute pathname, which avoids any need for the RUN statement to search PROPATH each time.

See also 

MEMBER function, SEARCH function