Language Environment Enhancements for OS/390 & VM V2R4

• Enabling Support for Contents

  This RAS improvement in OS/390 Version 2 Release 4 provides a new function called run-time library services (RTLS). This function allows customers to use multiple levels of the Language Environment run-time library during application execution. Customers will no longer need to STEPLIB and maintain their JCL to access different levels of Language Environment run-time libraries. Instead, with the use of new system parameters (PARMLIB) and new run-time options, customers can dynamically control which level of Language Environment run-time libraries are to be used on an individual application basis. This function also provides an alternative to placing the Language Environment run-time library in the linklist concatenation.




• New Run-Time Options

  The following run-time options were added:

  • RTLS(YES|NO)

    RTLS(YES) indicates to Language Environment to load the Language Environment run-time modules from the specified RTLS library and version.

    RTLS(NO), the system default, indicates to Language Environment that the conventional MVS loads (Non-RTLS) are to be done to load in the Language Environment run-time modules.

  • LIBRARY(library-name)

    Specifies the name of a RTLS defined logical library where Language Environment run-time modules and application modules are to be loaded from.

  • VERSION(version)

    Specifies the name of a RTLS logical library version to use. This option is not required. The default version is used when the option is not specified.

  • HEAPPOOLS (Available through APARs PQ04514 and PQ04657)

    Heap pools is an optional storage allocation algorithm for C/C++ applications that is much faster (in most circumstances ) than the normal malloc()/free() algorithm. Multi-threaded applications will get the most benefit from this option because proper use of heap pools virtually elminates contention for heap storage.