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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 the QNX OS 8.0.
Utilities & Libraries
C Library Reference
R

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX 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 the QNX OS 8.0.
- Quickstart Guide
- System Architecture
  The System Architecture guide accompanies the QNX OS and is intended for both application developers and end-users.
- OS Components & Operations
- Graphics
- Programming
- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX OS system and developers who want to create a QNX OS resource manager free from vulnerabilities.
- Utilities & Libraries
  - C Library Reference
    - What's in a Function Description?
    - Manifests
    - Character Sets
    - A
    - B
    - C
    - D
    - E
    - F
    - G
    - H
    - I
    - J
    - K
    - L
    - M
    - N
    - O
    - P
    - Q
    - R
      - raise()
        Generate a signal
      - rand()
        Generate a pseudo-random integer
      - rand_r()
        Generate a pseudo-random integer in a thread-safe manner
      - random()
        Generate a pseudo-random number from the default state
      - rdchk()
        Check to see if a read is likely to succeed
      - re_comp()
        Compile a regular expression
      - re_exec()
        Execute a regular expression
      - read()
        Read bytes from a file
      - readblock()
        Read blocks of data from a file
      - readcond()
        Read data from a terminal device
      - readdir(), readdir64()
        Read a directory entry
      - _readdir_r(), _readdir64_r()
        Read a directory and get stat information
      - readdir_r(), readdir64_r()
        Read a directory (reentrant)
      - readlink()
        Place the contents of a symbolic link into a buffer
      - readlinkat()
        Place the contents of a symbolic link found at a given location into a buffer
      - readv()
        Read bytes from a file
      - realloc()
        Allocate, reallocate, or free a block of memory
      - reallocarray()
        Allocate or reallocate a block of memory occupied by an array
      - realpath()
        Resolve a pathname
      - recallocarray()
        Allocate or reallocate a block of memory occupied by an array, and ensure that any newly allocated or released memory is cleared
      - regcomp()
        Compile a regular expression
      - regerror()
        Explain a regular expression error code
      - regexec()
        Compare a string with a compiled regular expression
      - regfree()
        Release memory allocated for a regular expression
      - _register_ioctl_handler()
        Register an I/O control handler
      - remainder(), remainderf(), remainderl()
        Compute the floating point remainder
      - remove()
        Remove a link to a file
      - remque()
        Remove an element from a doubly linked queue
      - remquo(), remquof(), remquol()
        Compute the floating point remainder
      - rename()
        Rename a file
      - renameat()
        Rename a file at a given location
      - resmgr_attach()
        Attach a path to the pathname space
      - resmgr_block()
        Block while waiting for a message
      - resmgr_connect_funcs_t
        Table of POSIX-level connect functions
      - resmgr_context_alloc()
        Allocate a resource-manager context
      - resmgr_context_free()
        Free a resource-manager context
      - resmgr_context_t
        Context information that's passed between resource-manager functions
      - resmgr_detach(), resmgr_detach_ctp()
        Remove a pathname from the pathname space
      - resmgr_devino()
        Get the device and inode number
      - resmgr_handler()
        Handle resource manager messages
      - resmgr_io_funcs_t
        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
      - resmgr_msggetsize()
        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
      - resmgr_msgreplyv()
        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
      - rint(), rintf(), rintl()
        Round to the nearest integral value
      - rmdir()
        Delete an empty directory
      - round(), roundf(), roundl()
        Round a number to the closest integer
      - 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
    - S
    - T
    - U
    - V
    - W
    - X
    - Y
    - Z
    - Full Safety Information
    - Glossary
  - Devctl and Ioctl Commands
  - JSON Library Reference
  - PAM Reference
  - QNX Helpers Developer's Guide
    These libraries provide QNX helpers, including helpers that assist with logging, string conversion, and number and type sizes.
  - SPI Framework Technote
  - QNX Cryptography Library
    The QNX Cryptography Library (qcrypto) is a flexible cryptography framework that allows you to choose which cryptography provider responds to requests on a per-process basis.
  - QNX devcrypto Service
  - 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.
- Migrating to QNX OS 8.0
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX OS in the Amazon cloud environment.
QNX Toolkit for Visual Studio Code
This User's Guide describes the QNX^® Toolkit for Visual Studio Code. The guide introduces you to the QNX Toolkit by explaining the QNX development environment and how to build, run, and debug your QNX^® Operating System (OS) applications and systems.
QNX Hypervisor User's Guide
This User's Guide explains the QNX hypervisor architecture and provides instructions for installing and running a QNX Hypervisor system, changing system components and configuration, and using hypervisor features such as virtual devices (vdevs).
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

R

QNX SDP8.0C Library ReferenceAPIDeveloper

The functions, macros, and data structures in the C library are described here in alphabetical order:

A ¦ B ¦ C ¦ D ¦ E ¦ F ¦ G ¦ H ¦ I ¦ J ¦ K ¦ L ¦ M ¦ N ¦ O ¦ P ¦ Q ¦ R ¦ S ¦ T ¦ U ¦ V ¦ W ¦ X ¦ Y ¦ Z

The following are described elsewhere:


For information about:	See:
random _source_init(), random _source_stop()	random in the Utilities Reference
recv(), recvfrom(), recvmmsg(), recvmsg()	FreeBSD documentation (https://man.freebsd.org/cgi/man.cgi?query=recv&manpath=FreeBSD+13.5-RELEASE+and+Ports) and Networking APIs in the High-Performance Networking Stack (io-sock) User's Guide.
res_init(), res_mkquery(), res_query(), res_querydomain(), res_search(), res_send()	FreeBSD documentation (https://man.freebsd.org/cgi/man.cgi?query=res_init&manpath=FreeBSD+13.5-RELEASE+and+Ports) and Networking APIs in the High-Performance Networking Stack (io-sock) User's Guide.
resmgr_attr_t	resmgr_attach()
RMSK_CLR()	ThreadCtl()
RMSK_ISSET()	ThreadCtl()
RMSK_SET()	ThreadCtl()
RMSK_SIZE()	ThreadCtl()
route	FreeBSD documentation (https://man.freebsd.org/cgi/man.cgi?query=route&sektion=4&manpath=FreeBSD+13.5-RELEASE+and+Ports)

This chapter describes the API components whose names begin with R.

Page updated: August 11, 2025