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Utilities & Libraries
C Library Reference
R
rand_r()
Generate a pseudo-random integer in a thread-safe manner

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.
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        Generate a signal
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        Generate a pseudo-random integer
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        Generate a pseudo-random integer in a thread-safe manner
      - random()
        Generate a pseudo-random number from the default state
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        Compile a regular expression
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        Explain a regular expression error code
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        Read a message from a client
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        Reply to a client with a message, endian-swapping if required
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        Write a message to a client
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        Write a message to a client
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        Indicate how many parts from the ctp->iov structure to return to the client
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        Retrieve an Open Control Block
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        Extract the OCB and I/O function pointers associated with the client connection
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        Associate an OCB with an open request
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        Return the pathname associated with an ID
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        Request to pause a message
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        Run a callback to resume processing of a paused message
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        Get one part from the ctp->iov structure and fill in its fields
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        Disassociate an OCB from an open request
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        Rewind a directory stream to the start of the directory
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        Round to the nearest integral value
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        Delete an empty directory
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        Round a number to the closest integer
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        Reserve a system resource for a process
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        Destroy a system resource
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        Return a system resource to the resource database
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        Get major and minor device numbers
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        Detach a major and minor number
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        Query the resource database
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rand_r()

QNX SDP8.0C Library ReferenceAPIDeveloper

Generate a pseudo-random integer in a thread-safe manner

Synopsis:

#include <stdlib.h>

int rand_r( unsigned int* seed );

Arguments:

seed: A pointer to the seed for the sequence of pseudo-random numbers. If you call rand_r() with the same initial value for the seed, the same sequence is generated.

Library:

libc

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

Description:

The rand_r() function computes, in a thread-safe manner, a sequence of pseudo-random integers in the range 0 through RAND_MAX.

Returns:

A pseudo-random integer.

Classification:

POSIX 1003.1 OB. This function is marked as obsolescent, and may be removed from a future version of the standard.


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 09, 2024