IBM PASE for i concepts
PASE for i is an integrated runtime environment for AIX® applications running on the IBM® i operating system.
PASE for i supports the application binary interface (ABI) of AIX and provides a broad subset of the support provided by AIX shared libraries, shells, and utilities. PASE for i also supports the direct processing of IBM PowerPC® machine instructions, so it does not have the drawbacks of an environment that only emulates the machine instructions.
PASE for i applications:
- Can be written in C, C++, Fortran, or PowerPC assembler
- Use the same binary executable format as AIX PowerPC applications
- Run in an IBM i job
- Use IBM i system functions, such as file systems, security, and sockets
Keep in mind that PASE for i is not a UNIX operating system on the IBM i operating system. PASE for i is designed to run AIX programs on the IBM i operating system with little or no change. Programs from any other environment, such as UNIX or Linux, need to be written such that they can be compiled on AIX as the first step toward running in PASE for i.
The PASE for i integrated run time runs on the Licensed Internal Code kernel on the IBM i operating system. The system provides integration of many common IBM i functions across PASE for i and other runtime environments (including Integrated Language Environment® (ILE) and Java™). PASE for i implements a broad subset of AIX system calls. System support for PASE for i enforces system security and integrity by controlling what memory an PASE for i program can access and restricting the program to use only unprivileged machine instructions.
Rapid application deployment with minimal effort
In many cases, your AIX programs can run in PASE for i with little or no change. The level of AIX programming skills you need varies depending on the design of your AIX program. In addition, by providing additional IBM i application integration in your program design (for instance, with CL commands), you can minimize configuration concerns for your application users.
PASE for i adds another porting option for solution developers who want to share in the success of the IBM i marketplace. By providing a means to cut porting time significantly, PASE for i can improve the time to market and return on investment for solutions developers.
A broad subset of AIX technology on IBM i
PASE for i implements an application run time that is based on a broad subset of AIX technology, including:
- Standard C and C++ run time (both threadsafe and non-threadsafe)
- Fortran run time (both threadsafe and non-threadsafe)
- pthreads threading package
- iconv services for data conversion
- Berkeley Software Distributions (BSD) equivalent support
- X Window System client support with Motif widget set
- Pseudo terminal (PTY) support
Applications are developed and compiled on an AIX workstation running a level of AIX that is compatible with a level supported by PASE for i, and then these applications are run on the IBM i operating system.
Alternatively, you can install one of the supported compiler products in the PASE for i environment to develop, compile, build, and run your applications completely within PASE for i.
PASE for i also includes the Korn, Bourne, and C shells and nearly 200 utilities that provide a powerful scripting environment.
PASE for i uses IBM investment in a common processor technology for the AIX and IBM i operating systems. The PowerPC processor switches from IBM i mode into AIX mode to run an application in the PASE for i run time.
Applications running in PASE for i are integrated with the IBM i integrated file system and DB2® for i. They can call (and be called by) Java and ILE applications. In general, they can take advantage of all aspects of the IBM i operating environment, such as security, message handling, communication, and backup and recovery. At the same time, they take advantage of application interfaces that are derived from AIX interfaces.