pfm_$intro(3)

NAME

pfm_$intro − fault management

SYNOPSIS

C Syntax

#include <idl/c/base.h>
#include <ppfm.h>

Remarks

To view this manual entry via the man(1) command, use the function name shown above without the “$” character.

DESCRIPTION

pfm_$() calls, part of the Network Computing System (NCS), allow programs to manage signals, faults, and exceptions by establishing cleanup handlers.

pfm_$cleanup() Establish a cleanup handler.

pfm_$enable() Enable asynchronous faults.

pfm_$enable_faults()
Enable asynchronous faults after faults have been inhibited via pfm_$inhibit_faults().

pfm_$inhibit() Inhibit asynchronous faults.

pfm_$inhibit_faults()
Inhibit asynchronous faults but allow time-sliced task switching.

pfm_$init() Initialize the PFM package.

pfm_$reset_cleanup()
Reset a cleanup handler.

pfm_$rls_cleanup()
Release cleanup handlers.

pfm_$signal() Signal the calling process.

Cleanup Handlers

A cleanup handler is a piece of code that allows a program to terminate gracefully when it receives an error. A cleanup handler begins with a pfm_$cleanup() call and usually ends with a call to pfm_$signal() or pgm_$exit(), though it can also simply continue back into the program after the cleanup code.

Include Files in NCS Software

<ppfm.h>, is the include file for the "portable PFM" interface. It supersedes <pfm.h>, the include file that was provided in early releases of NCS .

Constants

pfm_$init_signal_handlers
A constant used as the flags parameter to pfm_$init(), causing C signals to be intercepted and converted to PFM signals.

Data Types

pfm_$cleanup_rec
An opaque data type for passing process context among cleanup handler calls.

status_$t
A status code. Most NCS calls supply their completion status in this format. The status_$t type is defined as a structure containing a long integer:

struct status_$t {
long all;
}

However, the calls can also use status_$t as a set of bit fields. To access the fields in a returned status code, assign the value of the status code to a union defined as follows:

typedef union {
    struct {
        unsigned fail : 1,
                 subsys : 7,
                 modc : 8;
        short    code;
    } s;
    long all;
} status_u;

where:

all All 32 bits in the status code. If all is equal to status_$ok, the call that supplied the status was successful.

fail If this bit is set, the error was not within the scope of the module invoked, but occurred within a lower-level module.

subsys This indicates the subsystem that encountered the error.

modc This indicates the module that encountered the error.

code This is a signed number that identifies the type of error that occurred.

Status Codes

pfm_$bad_rls_order
Attempted to release a cleanup handler out of order.

pfm_$cleanup_not_found
There is no pending cleanup handler.

pfm_$cleanup_set
A cleanup handler was established successfully.

pfm_$cleanup_set_signalled
Attempted to use pfm_$cleanup_set as a signal.

pfm_$invalid_cleanup_rec
Passed an invalid cleanup record to a call.

pfm_$no_space
Cannot allocate storage for a cleanup handler.

status_$ok
The call was successful.

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