iofunc_client_info

Return information about a client connection, including abilities

Synopsis:

#include <sys/iofunc.h>

int iofunc_client_info_able ( resmgr_context_t * ctp,
                              const int ioflag,
                              struct _client_info ** info,
                              int flags,
                              struct _client_able abilities[],
                              const int nable );

Arguments:

ctp

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

ioflag

Zero, or the constant O_REALIDS. This argument is passed in the _IO_OPEN message during an open request. If you specify O_REALIDS, iofunc_client_info_able() swaps the real and effective values of the user and group IDs before returning. This is a QNX Neutrino extension, to swap real and effective user and group IDs in an atomic operation.

info

The address of a location where the function can store a pointer to a _client_info structure that the function can fill with information about the client. For information about this structure, see ConnectClientInfoExt(). The iofunc_client_info_able() function sets the _NTO_CI_UNABLE bit in the flags member if the client doesn't have all the indicated abilities.

flags

Zero or more of the following:

_NTO_CLIENTINFO_GETGROUPS — get the supplementary group IDs
_NTO_CLIENTINFO_GETTYPEID — results in the type identifier being returned immediately after the last returned supplementary group ID

abilities

An array of struct _client_able structures that specifies the abilities that the client must have; see ConnectClientInfoAble().

nable

The number of entries in the abilities array. Currently, the maximum supported value is 100.

Library:

libc

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

Description:

The iofunc_client_info_able() function fetches the info structure for the client, including its abilities. It calls ConnectClientInfoAble() to gather the information, based on the server connection ID found in ctp->info.scoid.

A server should test if the client has a specific ability only when it receives a request to perform a task that requires this ability, and not any sooner. For an explanation of why this is so, see the ConnectClientInfoAble() description.

Call iofunc_client_info_ext_free() to free the _client_info structure when you're done with it.

Returns:

EFAULT: A fault occurred when the kernel tried to access the info buffer provided.
EINVAL: The client process is no longer valid.
ENOMEM: The function couldn't allocate the memory for the _client_info structure.
EOK: Successful completion.
E2BIG: The nable parameter has exceeded 100 entries in the abilities array.

Classification:

QNX Neutrino

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	Yes
Thread	Yes