Content-type: text/html Man page of rsm_get_segmentid_range

rsm_get_segmentid_range

Section: Remote Shared Memory Library Functions (3RSM)
Updated: 8 May 2003
Index Return to Main Contents
 

NAME

rsm_get_segmentid_range - get segment ID range  

SYNOPSIS

cc [ flag... ] file... -lrsm [ library... ]
#include <rsmapi.h> 

int rsm_get_segmentid_range(const char *appid, rsm_memseg_id_t *baseid, uint32_t *length);  

DESCRIPTION

RSM segment IDs can be either specified by the application or generated by the system using the rsm_memseg_export_publish(3RSM) function. Applications that specify segment IDs require a reserved range of segment IDs that they can use. This can be achieved by using rsm_get_segmentid_range() and by reserving a range of segment IDs in the segment ID configuration file, /etc/rsm/rsm.segmentid. The rsm_get_segmentid_range() function can be used by applications to obtain the segment ID range reserved for them. The appid argument is a null-terminated string that identifies the application. The baseid argument points to the location where the starting segment ID of the reserved range is returned. The length argument points to the location where the number of reserved segment IDs is returned.

The application can use any value starting at baseid and less than baseid+length. The application should use an offset within the range of reserved segment IDs to obtain a segment ID such that if the baseid or length is modified, it will still be within its reserved range.

It is the responsibility of the system administrator to make sure that the segment ID ranges are properly administered (such that they are non-overlapping, the file on various nodes of the cluster have identical entries, and so forth.) Entries in the /etc/rsm/rsm.segmentid file are of the form:

#keyword             appid    baseid    length
reserved     SUNWfoo  0x600000  1000

The fields in the file are separated by tabs or blanks. The first string is a keyword "reserve", followed by the application identifier (a string without spaces), the baseid (the starting segment ID of the reserved range in hexadecimal), and the length (the number of segmentids reserved). Comment lines contain a "#" in the first column. The file should not contain blank or empty lines. Segment IDs reserved for the system are defined in the </usr/include/rsm/rsm_common.h> header and cannot be used by the applications.  

RETURN VALUES

Upon successful completion, these functions return 0. Otherwise, an error value is returned to indicate the error.  

ERRORS

The rsm_get_segmentid_range() function can return the following errors:

RSMERR_BAD_ADDR The address passed is invalid.

RSMERR_BAD_APPID The appid is not defined in configuration file.

RSMERR_BAD_CONF The configuration file is not present or not readable, or the configuration file format is incorrect.

 

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface StabilityUnstable
MT-LevelMT-Safe

 

SEE ALSO

rsm_memseg_export_publish(3RSM), attributes(5)


 

Index

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUES
ERRORS
ATTRIBUTES
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 02:38:34 GMT, October 02, 2010