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QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
Utilities & Libraries
C Library Reference
R
rindex()
Find the last occurrence of a character in a string

QNX Momentics IDE User's Guide
This User's Guide describes version 7.1 of the Integrated Development Environment (IDE) that's part of the QNX Momentics tool suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
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  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX Neutrino RTOS system and developers who want to create a QNX Neutrino resource manager free from vulnerabilities.
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  - Addon Interfaces Library Reference
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      - raise()
        Generate a signal
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        Generate a pseudo-random integer
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        Check to see if a read is likely to succeed
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        Execute a regular expression
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        Place the contents of a symbolic link into a buffer
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        Allocate, reallocate, or free a block of memory
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        Receive a message from a socket
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        Receive a message from the socket at a specified address
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        Receive multiple messages and their headers from a socket
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        Compile a regular expression
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        Compare a string with a compiled regular expression
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        Release memory allocated for a regular expression
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        Register an I/O control handler
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        Compute the floating point remainder
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        Remove a link to a file
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        Remove an element from a doubly linked queue
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        Compute the floating point remainder
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        Rename a file
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        Rename a file at a given location
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        Initialize the Internet domain name resolver routines
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        Construct an Internet domain name query
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        Query the local Internet domain name server
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        Query the local Internet domain name server
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        Query a local server, using search options
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        Send a preformatted Internet domain name query
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        Attach a path to the pathname space
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        Block while waiting for a message
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        Table of POSIX-level connect functions
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        Allocate a resource-manager context
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        Free a resource-manager context
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        Context information that's passed between resource-manager functions
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        Remove a pathname from the pathname space
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        Get the device and inode number
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        Expand the capacity of the device manager database
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        Tune aspects of client fd-to-OCB mapping
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        Handle resource manager messages
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        Table of POSIX-level I/O functions
      - resmgr_iofuncs()
        Extract the I/O function pointers associated with the client connection
      - resmgr_msg_again()
        Process a message again in a resource manager
      - resmgr_msgget()
        Read a message from a client, from local data, or both
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        Get the size of a message and its local and remote parts
      - resmgr_msggetv()
        Read a message from a client, from local data, or both
      - resmgr_msgread()
        Read a message from a client
      - resmgr_msgreadv()
        Read a message from a client
      - resmgr_msgreply()
        Reply to a client with a message, endian-swapping if required
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        Reply to a client with a message, endian-swapping if required
      - resmgr_msgwrite()
        Write a message to a client
      - resmgr_msgwritev()
        Write a message to a client
      - _RESMGR_NPARTS()
        Indicate how many parts from the ctp->iov structure to return to the client
      - resmgr_ocb()
        Retrieve an Open Control Block
      - resmgr_ocb_iofuncs()
        Extract the OCB and I/O function pointers associated with the client connection
      - resmgr_open_bind()
        Associate an OCB with an open request
      - resmgr_pathname()
        Return the pathname associated with an ID
      - _RESMGR_PTR()
        Get one part from the ctp->iov structure and fill in its fields
      - _RESMGR_STATUS()
        Set the status member of a resource-manager context
      - resmgr_unbind()
        Disassociate an OCB from an open request
      - rewind()
        Rewind a file stream to the beginning of the file
      - rewinddir()
        Rewind a directory stream to the start of the directory
      - rindex()
        Find the last occurrence of a character in a string
      - rint(), rintf(), rintl()
        Round to the nearest integral value
      - rmdir()
        Delete an empty directory
      - round(), roundf(), roundl()
        Round a number to the closest integer
      - ROUTE
        System packet forwarding database
      - rsrcdbmgr_attach()
        Reserve a system resource for a process
      - rsrcdbmgr_create()
        Create a system resource
      - rsrcdbmgr_destroy()
        Destroy a system resource
      - rsrcdbmgr_detach()
        Return a system resource to the resource database
      - rsrcdbmgr_devno_attach()
        Get major and minor device numbers
      - rsrcdbmgr_devno_detach()
        Detach a major and minor number
      - rsrcdbmgr_query_name()
        Query the resource database
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  - Devctl and Ioctl Commands
  - JSON Library Reference
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  - Utilities Reference
  - WPA Control Interface Reference
    This document provides a reference for the Wi-Fi Protected Access (WPA) control interface, which provides a C API for the WPA/IEEE 802.11i protocols in Wi-Fi client stations. Application developers who want to control WPA operations and get associated status and event data should read this reference.
QNX Hypervisor
The QNX Hypervisor allows you to run multiple OSs on a target system so you can separate critical and non-critical functions, support a wide variety of applications, and reduce hardware costs.
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX software in Amazon Web Services (AWS) and Microsoft Azure (Azure).
QNX Advanced Virtualization Frameworks User's Guide
This User's Guide is aimed at all systems integrators and developers who want to design and build embedded systems using the QNX Advanced Virtualization Frameworks.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation and explains how to obtain technical support.

rindex()

Find the last occurrence of a character in a string

Synopsis:

#include <strings.h>

char *rindex( const char *s, 
              int c );

Arguments:

s: The string you want to search. This string must end with a null (\0) character. The null character is considered to be part of the string.
c: The character you're looking for.

Library:

libc

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

Description:

The rindex() function returns a pointer to the last occurrence of the character c in the string s.

Returns:

A pointer to the character, or NULL if the character doesn't occur in the string.

Classification:

Standard Unix; removed from POSIX.1-2008


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

Page updated: March 12, 2026