About This Manual

This manual discusses several topics of interest to programmers writing applications for the IRIX operating system on Silicon Graphics computers. These topics include memory management, interprocess communication, models of parallel computation, file and record locking, font access, and internationalization.

What This Manual Contains

This manual contains the following major parts:

What You Should Know Before Reading This Manual

This manual assumes that you are writing an application that executes under IRIX version 6.2 or later, and that you are familiar with the programming conventions of UNIX in general and IRIX in particular.

All examples are in the C language, although the descriptions are valid for C++ or any other language that provides access to IRIX kernel functions, such as Silicon Graphics Ada95 or MIPSpro Fortran 90.

Other Useful References

In addition to this manual, which covers specific IRIX features, you will need to refer to Silicon Graphics manuals that describe compilers and programming languages. Some of the most useful are listed in Table i.

Table 1. Books for Further Reading in IRIX Development


Document Title


Overview of the IRIX library of manuals for developers

Programming on Silicon Graphics Systems: An Overview


Compiling, linking, and tuning programs in C, C++, or Fortran

MIPSpro Compiling and Performance Tuning Guide


Writing modules in assembly language.

MIPSpro Assembly Language Programmer's Guide


C language

C Language Reference Manual


C++ language

C++ Language System Overview


Fortran language

MIPSpro Fortran 77 Programmer's Guide



MIPSpro Fortran 90 Programmer's Guide


System Configuration

IRIX Admin: System Configuration and Tuning


Writing real-time applications

REACT/Pro Real Time Programmer's Guide


Controlling devices directly

IRIX Device Driver Programmer's Guide


Details of the MIPS processor hardware

MIPS R4000 Microprocessor User's Manual


You can find additional information about internationalization from X/Open Company Limited. X/Open Portability Guide, Volume 1, XSI Commands and Utilities, Volume 2; XSI System Interface; and Volume 3, XSI Supplementary Definitions. Berkshire, United Kingdom. Prentice-Hall, Inc.

Obtaining Manuals

Silicon Graphics manuals are usually read online using IRIS InSight. This manual and many of the books in Table i are installed as part of the IRIS Development Foundation feature. When the books are installed or mounted on your workstation, use the command iiv, or double-click the IRIS InSight icon, to launch IRIS Insight. Then select the book you want from the “bookshelf” display.

When the manuals are not accessible to your workstation you can examine or order any Silicon Graphics manual on the World Wide Web using the following URL: http://techpubs.sgi.com.

Conventions Used in This Manual

This manual uses the conventions and symbols shown in Table ii.

Table 2. Typographical Conventions

Type of Information

Example of Typography

Filenames and pathnames

This structure is declared in /usr/include/sys/time.h.

IRIX command names and options used in normal text

Update these variables with systune; then build a new kernel with autoconfig -vf.

Names of program variables, structures, and data types, used in normal text

Global variable mainSema points to an IRIX semaphore, which has type usema_t.

Names of IRIX system functions, library functions, and functions in example code

Use mmap() to map an object into the address space, and munmap() to remove it.

Names of IRIX reference (man) pages. You can click on any of these to display the page

See the plock(2) reference page.

When complete lines of example code or commands are set off from normal text, they are displayed as follows.

ipcrm -s semid 

Parts of the code or command that need to be typed exactly as shown are displayed in a monospaced font. Operands that you supply are italicized.

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