iofunc_mmap_default()

Default handler for _IO_MMAP messages

Synopsis:

#include <sys/iofunc.h>

int iofunc_mmap_default ( resmgr_context_t * hdr,
                          io_mmap_t * msg,
                          iofunc_ocb_t * ocb );

Arguments:

ctp

A pointer to a resmgr_context_t structure that the resource-manager library uses to pass context information between functions.

msg

A pointer to the io_mmap_t structure that contains the message that the resource manager received. For more information, see the documentation for iofunc_mmap().

ocb

A pointer to the iofunc_ocb_t structure for the Open Control Block that was created when the client opened the resource.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The iofunc_mmap_default() function provides functionality for the _IO_MMAP message. This message is private to the Memory Manager (a part of the Neutrino microkernel's procnto).

You can place this function directly into the io_funcs table passed to resmgr_attach(), at the mmap position, or you can call iofunc_func_init() to initialize all of the functions to their default values.

Note that if the Process Manager is to be able to execute from this resource, then you must use the iofunc_mmap() function.

The iofunc_mmap_default() function calls iofunc_mmap() to do the actual work.

Returns:

A nonpositive value (i.e. ≤ 0)

Successful completion.

EROFS

An attempt to memory map (mmap) a read-only file, using the PROT_WRITE page protection mode.

EACCES

The client doesn't have the appropriate permissions.

ENOMEM

Insufficient memory exists to allocate internal resources required to effect the mapping.

Classification:

QNX Neutrino

See also:

iofunc_func_init(), iofunc_mmap(), iofunc_ocb_t, resmgr_attach(), resmgr_context_t, resmgr_io_funcs_t

Writing a Resource Manager

Resource Managers chapter of Getting Started with QNX Neutrino