Standards
| Standards / Extensions |
C or C++ |
Dependencies |
|---|
Language Environment
|
both |
OS/390 V2R9 |
Format
#include <sys/__cpl.h>
int __cpl(int functioncode, int bufferlen, char *buffer);
General description
__cpl() is currently
called by the CFSizer (Coupling Facility structure sizer) tool. An IBM® customer answers a minimum set of questions
from an IBM web page, about
one or more IBM products and
then clicks the submit button. The
submit invokes
a C
cgi program that parses the data, calls
__cpl() to Query the Coupling Facility or size one or more Coupling
Facility structures and then display the results back to the web client
browser.
- functioncode
- A value that specifies what function BPX1CPL will perform. The
following function codes are defined.
- CPL_QUERY (equates to value of 1)
- CPL_CFSIZER (equates to a value of 2)
- CPL_CFSIZER_W_LVL (equates to a value of 3)
CFlevel8 or higher is required to use the computesize function.
To provide a consistent result, the code must loop through all online
CFs and find the one at the highest CF level. Issuing computesize
against CFs at different levels gives different sizes back to the
user resulting in inconsistent results when multiple requests are
issued.
- bufferlen
- The length of the input/output storage area (buffer)
for BPX1CPL
- buffer
- Storage area for input/output for BPX1CPL
__cpl()
is an interface to the BPX1CPL Assembler Callable Service. For more
information on parameters and behavior of BPX1CPL, please refer to z/OS UNIX System Services Programming: Assembler Callable Services Reference.
Returned value
If successful, __cpl() returns
0.
If unsuccessful, __cpl() returns -1 and sets errno to one
of the following values:
- Error Code
- Description
- EFAULT
- One of the parameters contained an address that was not accessible
to the caller.
- EINVAL
- The functioncode parameter contains
a value that is not correct.
- EMVSCPLERROR
- A __cpl() service failed.
- ENOSYS
- The __cpl() service failed because the system is not at the correct
level.
- EPERM
- The calling thread's address space is not permitted.
Usage notes
- Access to __cpl() is controlled using a new RACF® class profile BPX.CF. For any of these
cases to run, a BPX.CF class profile must be created and access level
provided.
__cpl() is only valid on a Parallel Sysplex® enabled system
with a CFlevel 8 or higher Coupling Facility. Most installations run
with two or more Coupling Facilities for availability and recoverability
reasons. As such, the code was designed to provide the flexibility
of allowing the caller to specify a CF or if not specified, MVS™ will select the first CF at CFlevel
8 it finds.