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Utilities & Libraries
C Library Reference
I
iofunc_client_info_ext()
Return information about a client connection

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        Check access permissions
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        Handle an _IO_CHMOD message
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        Default handler for _IO_CHMOD messages
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        Handle an _IO_CHOWN message
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        Default handler for _IO_CHOWN messages
      - iofunc_client_info_able()
        Return information about a client connection, including abilities
      - iofunc_client_info_ext()
        Return information about a client connection
      - iofunc_client_info_ext_free()
        Free the structure used for information about a client connection
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        Free all locks allocated for the client process
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        Default handler for _IO_CLOSE messages
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        Return the memory allocated for an OCB
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        Return the memory allocated for an OCB
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        Default handler for _IO_DEVCTL messages
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        Perform validation that's common to all handlers for _IO_DEVCTL messages
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        Default handler for _IO_FDINFO messages
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        Link two directory entries
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        Handle an _IO_LSEEK message
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        Default handler for _IO_LSEEK messages
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        Verify a client's ability to make a new filesystem entry point
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        Open Control Block structure
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        Verify a client's ability to open or to create a resource
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        Default handler for _IO_CONNECT messages
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        Increment count and locking flags
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        Default handler for _IO_OPENFD messages
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        Support pathconf() requests
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        Default handler for _IO_PATHCONF messages
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        Default handler for _IO_READ messages
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        Verify a client's read access to a resource
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        Verify the attributes being used to read a link
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        Do permission checks for a _IO_CONNECT_RENAME message
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        Do permission checks for the _IO_SPACE message
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        Populate a stat structure
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        Default handler for _IO_STAT messages
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        Indicate if synchronization is needed
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        Default handler for _IO_SYNC messages
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        Verify permissions to sync
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        Update time stamps
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        Unblock OCBs
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        Default unblock handler
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        Verify that an entry can be unlinked
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        Default handler for the unlock_ocb callout
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        Update time stamps
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        Default handler for _IO_UTIME messages
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        Default handler for _IO_WRITE messages
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        Verify a client's write access to a resource
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        Arm a resource manager
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        Test a character to see if it's alphanumeric
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        Test a character to see if it's alphabetic
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        Test a character to see if it's a 7-bit ASCII character
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        Test a character to see if it's a blank character
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        Test a character to see if it's a control character
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        Test a character to see if it's a decimal digit
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        Test the file type of a file descriptor
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        Determine if a number is finite
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        Test a character to see if it's any printable character except a space
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        Determine whether one floating-point number is greater than another
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        Determine whether one floating-point number is greater than or equal to another
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        Test for infinity
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        Determine whether one floating-point number is less than another
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        Determine whether one floating-point number is less than or equal to another
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        Determine whether one floating-point number is less than or greater than another
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        Test a character to see if it's a lowercase letter
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        Test for not-a-number (NaN)
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        Determine whether a floating-point number is normal
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        Test a character to see if it's any printable character, including a space
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        Determine whether two floating-point numbers are unordered
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iofunc_client_info_ext()

QNX SDP8.0C Library ReferenceAPIDeveloper

Return information about a client connection

Synopsis:

#include <sys/iofunc.h>

int iofunc_client_info_ext ( resmgr_context_t * ctp,
                             const int ioflag,
                             struct _client_info ** info,
                             int flags );

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_ext() swaps the real and effective values of the user and group IDs before returning. This is a QNX OS 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().

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

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_ext() function fetches the info structure for the client. It calls ConnectClientInfoExt() to gather the information, based on the server connection ID found in ctp->info.scoid.

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.

Classification:


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 11, 2025