API Introduction

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DESCRIPTION

These reference pages describe the functions provided with the MKS Toolkit UNIX APIs. The page for each function describes the MKS Toolkit UNIX APIs implementation of that function.

This introductory page discusses some common topics, such as standards conformation, error code mapping, signal mapping, global system variables, the environment, and clocks and timers.

Standards Conformance

Each page lists the standard to which the MKS Toolkit UNIX APIs implementation was written. For most pages, the standard is one of the following:

MKS Toolkit UNIX APIs Extension

A MKS Toolkit UNIX APIs extension to the standard APIs.

UNIX 98

The Single UNIX Specification, Version 2, from The Open Group.

UNIX 03

The Single UNIX Specification, Version 3, from The Open Group.

POSIX.1 (1996)

The 1996 re-issue of the ISO/IEC 9945-1 standard (also ANSI/IEEE Std 1003.1), for the Portable Operating System Interface (Part 1: System Application Programming Interface). This encompasses the earlier 1988 release of POSIX.1, with the subsequently-standardized real-time and threading interfaces added.

POSIX.2 (1992)

ANSI/IEEE Std 1003.2, for the Portable Operating System Interface (Part 2: Shell and Utilities).

ANSI/ISO 9899-1990

The American National Standard for Programming Languages — C. This is the 1990 re-issue of the ANSI C language standard for alignment with the international standards body.

ANSI/ISO 9899-1990/AM 1-1995

The American National Standard for Programming Languages — C — Amendment 1: C Integrity. This amendment to the C language standard specifies extensions to the language and library to support internationalized applications.

4.4BSD

The 4.4BSD-Lite2 implementation of UNIX from The University of California at Berkeley.

SVR3 or SVR4

Taken from the documentation for the System V Release 3 or System V Release 4 implementations of UNIX from AT&T.

Multithread Safety Level

Each page lists the multithread safety level of the functions described on that page. The level is one of the following:

Unsafe:

The function uses global or static state that is not protected. It is not safe to use unless the application ensures that only one thread at a time executes the function.

MT-safe:

The function is prepared for multithreaded access. A multithreaded application can safely call the function from multiple threads; the function will provide any necessary concurrency controls

Async-signal-safe:

An async-signal-safe function is one that can be safely called from a signal handler. A thread that is executing an async-signal-safe function will not deadlock with itself if interrupted by a signal. Calling any function that is not marked as async-signal-safe from a signal handler results in undefined program behavior.

Async-cancel-safe:

An async-cancel-safe function is one that can be safely called while asynchronous thread cancellation is enabled (refer to pthread_cancel() for more information on thread cancellation). Calling any function that is not marked as async-cancel-safe while asynchronous thread cancellation is enabled results in undefined program behavior.

Any exceptions to these definitions is noted for each function.

Supported Signals

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SEE ALSO

MKS Toolkit

Commands