About This Manual

This manual provides information on implementing FORTRAN 77 programs using the MIPSpro Fortran 77 compiler on the IRIX Operating System, Version 6.2 and above. This implementation of FORTRAN 77 contains full American National Standards Institute (ANSI) Programming Language Fortran (X3.9-1978) (in June, 1997, ANSI no longer supported this standard). Extensions provide full VMS Fortran compatibility to the extent possible without the VMS operating system or VAX data representation. This implementation of FORTRAN 77 also contains extensions that provide partial compatibility with programs written in SVS Fortran. This book also describes the Auto-Parallelizing Option (APO) which is an optional software product available for purchase.

The MIPSpro Fortran 77 compiler supports the -n32 and -n64 ABI (Application Binary Interface). The Fortran 77 compiler supports only the -o32 ABI.

Related Publications

The following documents contain additional information that may be helpful:

  • The MIPSPro Fortran 77 Language Reference Manual provides a description of the FORTRAN 77 language as implemented on Silicon Graphics systems.

  • The MIPSpro Compiling and Performance Tuning Guide provides information about improving program performance by using the optimization facilities of the compiler system, the dump utilities, archiver, debugger, and the tools used to maintain Fortran programs.

  • The MIPSpro 64-Bit Porting and Transition Guide provides an overview of the 64-bit compiler system and language implementation differences, porting source code to the 64-bit system, compilation and run-time issues.

  • The MIPSPro 7 Fortran 90 Commands and Directives Reference Manual provides information about the Fortran 90 and 95 compiler.

  • The f77(1), abi(5), lno(5), o32(5), opt(5), and pe_environ(5) man pages

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The following conventions are used throughout this document:




This fixed-space font denotes literal items such as commands, files, routines, path names, signals, messages, and programming language structures.


Italic typeface denotes variable entries and words or concepts being defined.

user input 

This bold, fixed-space font denotes literal items that the user enters in interactive sessions. Output is shown in nonbold, fixed-space font.

[ ] 

Brackets enclose optional portions of a command or directive line.


Ellipses indicate that a preceding element can be repeated.

The default shell in the UNICOS and UNICOS/mk operating systems, referred to as the standard shell, is a version of the Korn shell that conforms to the following standards:

  • Institute of Electrical and Electronics Engineers (IEEE) Portable Operating System Interface (POSIX) Standard 1003.2-1992

  • X/Open Portability Guide, Issue 4 (XPG4)

The UNICOS and UNICOS/mk operating systems also support the optional use of the C shell.

Cray UNICOS Version 10.0 is an X/Open Base 95 branded product.

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