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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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C Library Reference
C
closelog()
Close the syslogd system log

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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        Compute the complex inverse hyperbolic tangent
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        Set a clock
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        Adjust the time of a clock
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        Get the number of clock cycles
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        Get the CPU-time clock ID for a given process and thread
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        Get or set a clock period
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        Get or set a clock
      - clog(), clogf(), clogl()
        Compute the complex natural (base-e) logarithm of a complex number
      - close()
        Close a file
      - closedir()
        Close a directory
      - closelog()
        Close the syslogd system log
      - _cmdname()
        Find the path used to invoke the current process
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        Create a complex number from its real and imaginary parts
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        Unblock threads waiting on a condition
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        Destroy a condition variable
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        Initialize a condition variable
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        Unblock a thread that's waiting on a condition variable
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        Wait on a condition variable, with a time limit
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        Wait on a condition variable
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        Get configuration-defined string values
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        Compute the complex conjugate of a complex number
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        Initiate a connection on a socket
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        Establish a connection between a process and a channel
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        Get information about a client connection
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        Get extended information about a client connection, including abilities
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        Get extended information about a client connection
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        Break a connection between a process and a channel
      - ConnectFlags(), ConnectFlags_r()
        Modify or query the flags associated with a connection
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        Get information about a server connection
      - copysign(), copysignf(), copysignl()
        Copy the sign bit from one number to another
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        Compute the cosine of an angle
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        Compute the hyperbolic cosine
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        Raise a complex number to the power of another complex number
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        Compute the projection of a complex number on the Riemann sphere
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        Compute the real part of a complex number
      - creat(), creat64()
        Create and open a file (low-level)
      - crypt()
        Hash a password
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        Compute the complex sine
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        Compute the complex hyperbolic sine
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        Compute the square root of a complex number
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        Compute the complex tangent
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        Compute the complex hyperbolic tangent
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        Generate the path name of the current controlling terminal
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        Convert calendar time to local time
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QNX Advanced Virtualization Frameworks User's Guide
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Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation and explains how to obtain technical support.

closelog()

Close the syslogd system log

Synopsis:

#include <syslog.h>

void closelog( void );

Library:

libc

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

Description:

The closelog() function closes the connection to the syslogd system log.

Classification:

POSIX 1003.1


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

Page updated: March 12, 2026