Content-type: text/html Man page of mvalid

mvalid

Section: System Calls (2)
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NAME

mvalid - Checks memory region for validity  

SYNOPSIS

#include <sys/types.h>

#include <sys/mman.h>

int mvalid (        caddr_t addr,
       size_t len,
       int prot );
 

PARAMETERS

Specifies the address of the region whose validity is to be checked. Specifies length in bytes of the region specified by the addr parameter. Specifies the desired access protection for the region.  

DESCRIPTION

The mvalid() function checks the validity of a memory region. A region is considered to be valid if accesses of the requested type are allowed to all addresses in the region.

The sys/mman.h header file defines the following access options: The mapped region can be read. The mapped region can be written. The mapped region can be executed.

The prot parameter can be any combination of PROT_READ, PROT_WRITE, and PROT_EXEC ORed together.  

RETURN VALUES

The mvalid() function returns 0 (zero) if accesses requiring the specified protection are allowed to all addresses within the specified range of addresses. Otherwise, the mvalid() function returns -1 and sets errno to indicate the error.  

ERRORS

If the mvalid() function fails, errno may be set to one of the following values: The range specified by [addr, addr + len) is invalid for the process' address space, or the range specifies one or more unmapped pages, or one or more pages of the range disallows accesses of the specified protection. The prot parameter is invalid, or the addr parameter is not a multiple of the page size as returned by sysconf(_SC_PAGE_SIZE).  

RELATED INFORMATION

Functions: mmap(2), mprotect(2), sysconf(3) delim off


 

Index

NAME
SYNOPSIS
PARAMETERS
DESCRIPTION
RETURN VALUES
ERRORS
RELATED INFORMATION

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Time: 02:40:12 GMT, October 02, 2010