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Full Discussion: FIFO write and read
Top Forums Programming FIFO write and read Post 302815613 by ebasse2 on Saturday 1st of June 2013 12:39:22 PM
Old 06-01-2013
FIFO write and read

Can someone help me to write this program in C in QNX?

Using the FIFO queues write a simple communication system consisting of programs write and read. The program write the parameters given strings enclosed in single quotes. These strings are written to the FIFO file. Reads the program read them from there. Programs should behave as in the following example.

$write ‘write1'
$read
read 1
$

I dont know how to do it, but need this program to pass an exam ;(
 

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pthread_rwlockattr_init(3T)											       pthread_rwlockattr_init(3T)

NAME
pthread_rwlockattr_init(), pthread_rwlockattr_destroy() - initialize or destroy a read-write lock attributes object SYNOPSIS
PARAMETERS
attr Pointer to the read-write lock attributes object to be initialized or destroyed. DESCRIPTION
initializes the read-write lock attributes object attr with the default value for all attributes. The attributes object describes a read- write lock in detail and is passed to the read-write lock initialization function. When a read-write lock attributes object is used to initialize a read-write lock, the values of the individual attributes determine the characteristics of the new read-write lock. Attributes objects act like additional parameters to object initialization. After a read-write lock attributes object has been used to initialize one or more read-write lock, any function affecting the attributes object does not affect the previously initialized read-write locks. The read-write lock attributes and their default values are: The default value is If an initialized read-write lock attributes object is reinitialized, undefined behavior results. destroys the read-write lock attributes object attr. The destroyed read-write lock attributes object ceases to exist and its resources are reclaimed. Referencing the object after it has been destroyed results in undefined behavior. A destroyed read-write lock attributes object can be reinitialized using the function Read-write locks which have been already initialized using this attributes object are not affected by the destruction of the read-write lock attributes object. RETURN VALUE
Upon successful completion, and return zero. Otherwise, an error number is returned to indicate the error (the variable is not set). ERRORS
For each of the following conditions, if the condition is detected, the and functions return the corresponding error number: [ENOMEM] There is insufficient memory available in which to initialize attr. [EINVAL] The value specified by attr is invalid. AUTHOR
and were developed by X/Open. SEE ALSO
pthread_create(3T), pthread_rwlockattr_getpshared(3T), pthread_rwlockattr_setpshared(3T), pthread_rwlock_init(3T). STANDARDS CONFORMANCE
Pthread Library pthread_rwlockattr_init(3T)
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