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Revision as of 17:00, 21 July 2009 by Overbey2.illinois.edu (Talk | contribs) (Starting a Project with a Hand-Written Makefile)

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Photran 5.0 User's Guide

IMPORTANT: PHOTRAN 5.0 HAS NOT BEEN PUBLICLY RELEASED. This is PRELIMINARY documentation for Photran 5.0's release in September, 2009. Parts of it DO NOT APPLY to the currently-available release.

Installing Photran

System Requirements

To install Photran 5.0...

You must have Eclipse 3.5 (Galileo) installed.

  1. You should have the C/C++ Development Tools (CDT) 6.0 installed. If you do not, they will be installed automatically when you install Photran.
  2. Eclipse must be running on a Java 1.5 or later Java Virtual Machine (JVM). To get reasonable performance, we recommend Sun's JVM [1] or IBM's [2]. GNU Classpath (the default JVM on Fedora Linux) is generally too slow to be useful.
  3. If you want to compile and build Fortran applications, you must have a make utility and a Fortran compiler in your system path. Many Linux/Unix systems include these; details on installing them in Windows and Mac are below.

Installation Procedure

To install Photran, start Eclipse, then...

  1. Download the latest Photran zip file from [3]
  2. Click on Help > Software Updates...
  3. Click on the "Available Software" tab
  4. Click on "Add Site..."
  5. Click Archive...
  6. Choose the zip file you downloaded from [4]
  7. Click OK to close the Add Site dialog
  8. The zip file should appear in the list as jar:file:/path/to/photran-master-4.0.5-something. Expand it.
  9. Expand "Photran (Eclipse Fortran Development Tools)" and check the box next to "Photran (Eclipse Fortran Development Tools)"
  10. If you are running Linux and have the Intel Fortran Compiler installed, or if you are on a Macintosh and have the IBM XL Fortran compiler installed, expand "Photran Compiler Support" and select the appropriate compiler.
  11. Click on the "Install..." button in the upper-right corner of the dialog box.

Additional Instructions for Windows Users

To compile and run Fortran programs in Photran, you will need to have a Fortran compiler and make utility installed. Most Linux/Unix distributions include these; gfortran is commonly used (and free). Under Windows, you will need to install Cygwin [5] or MinGW [6] and put them on your Windows PATH.
Instructions for Cygwin:

  1. Install [Cygwin http://www.cygwin.com/]; the defaults are mostly OK, but you will need to explicitly tell it to include the "Devel" packages (at least gcc4-fortran, gdb, and make) when the installer asks you to select what packages to install. (If gcc4-fortran is not listed under the "Devel" packages, you may have chosen a bad mirror; restart the Cygwin installation, and choose a different mirror instead. Georgia Tech's mirror at gtlib.gatech.edu is generally quite fast and reliable, for example.)
  2. Add the Cygwin directories to your Windows PATH. Under Windows XP, the process is as follows:
    1. Make sure you are logged in under an administrator account.
    2. Open the Control Panel.
    3. Double-click the System icon.
    4. Switch to the Advanced tab.
    5. Click the Environment Variables button.
    6. Under System Variables, find the variable "Path" in the list, and click on it.
    7. Click Edit.
    8. At the end of the "Variable Value" text, add
    9. Click OK, click OK, click OK, and close the Control Panel.
    10. Close and re-open Photran. Windows should now search C:\Cygwin\bin, C:\Cygwin\usr\bin, etc. when it's looking for executables (including make.exe, gcc.exe, and gfortran.exe).

Additional Instructions for Mac OS X Users

If you install gfortran on Mac OS X, it may be installed in /usr/local/bin, which is not (by default) on the PATH. If you are launching Eclipse from a Terminal, the PATH can be set by modifying /etc/paths. However, if you are launching Eclipse from the Finder (by double clicking on it) or the Dock, then the PATH is not obtained from the shell or /etc/paths. Instead, it's obtained from ~/.MacOSX/environment.plist. The format of the environment.plist file is as follows (change the path appropriately). If you create or edit this file, you will need to log out (or reboot) before the changes will take effect.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">

Starting a New Project

One of the advantages (or disadvantages) of using Photran is that it does not include a Fortran compiler. Instead, it uses make to compile Fortran programs. This allows you to use any Fortran compiler you want, but it also means that a Makefile must be written which tells the make program how to compile your Fortran program.

  • For small, simple projects, Photran can auto-generate a Makefile which will use the GNU Fortran compiler (gfortran).
  • For more complex projects, you can write a custom Makefile.

For more information, click on Help > Help Contents in Eclipse, and navigate to C/C++ Development User Guide > Concepts > CDT Projects.

Starting a Project with an Auto-Generated Makefile

The following is a typical procedure for starting a new project using an auto-generated Makefile. Your system must have the GNU Fortran (gfortran) compiler installed for this procedure to work. To make sure that gfortran is installed, you can open a command prompt (Windows) or terminal window (Linux/Mac) and type "gfortran" (without the quotes); it should respond with "gfortran: no input files".

  1. Click File > New > Fortran Project
  2. Call it HelloFortran
  3. Choose "Executable (Gnu Fortran)" from the project type list
  4. Choose "GCC Toolchain" from the toolchain list (you may need to first uncheck the "Show project types..." check box at the bottom of the window before you can see this)
  5. Click Next
  6. Click on Advanced Settings
  7. Expand C/C++ Build in the list on the left, and click on Settings
  8. Click on the Binary Parsers tab. Check the appropriate parsers for your platform. If you are using Windows, check PE Windows Parser and/or Cygwin PE Parser; if you are using Linux, check Elf Parser; if you are using Mac, check Mach-O parser.
  9. Click on the Error Parsers tab. Check the error parser(s) for the Fortran compiler(s) you will use.
  10. Click OK
  11. Click Finish
  12. Click File > New > Source File
  13. Call it hello.f90; click Finish
  14. Type the standard "Hello, World" program shown below, and click File > Save.
  15. Open the Console view, and make sure "make" ran OK and compiled your program
  16. In the Fortran Projects view, expand the Binaries entry, and click on your executable (e.g., "HelloFortran.exe - [x86le]")
  17. Run | Run As | Run Local Fortran Application
  18. Choose GDB Debugger (Cygwin GDB Debugger if you're under Windows)
  19. Check the Console view, and make sure "Hello World" appeared.


program hello
    print *, "Hello World"
end program

Starting a Project with a Hand-Written Makefile

The following is a typical procedure for starting a new project using a hand-written Makefile. The following example uses the GNU Fortran (gfortran) compiler, but any Fortran compiler can be used instead. We will assume that you are familiar with how to write a Makefile. If not, there are plenty of resources on the Web, including a tutorial from an introductory Computer Science course at UIUC [7] and another from the University of Hawaii [8]... and, of course, you can always read the entire manual for GNU Make [9].

  1. Click File > New > Fortran Project
  2. Call it HelloFortran
  3. Expand "Makefile project" in the project type list (it has a folder icon), and choose "Empty Project"
  4. Select "-- Other Toolchain --" in the toolchain list in the right-hand column, and click Next
  5. Click on Advanced Settings
  6. Expand C/C++ Build in the list on the left, and click on Settings
  7. Click on the Binary Parsers tab.  Check the appropriate parsers for your platform. If you are using Windows, check PE Windows Parser and/or Cygwin PE Parser; if you are using Linux, check Elf Parser; if you are using Mac, check Mach-O parser.
  8. Click on the Error Parsers tab. Check the error parser(s) for the Fortran compiler(s) you will use.
  9. Click OK
  10. Click Finish
  11. Click File > New > Source File
  12. Call it hello.f90
  13. Click Finish
  14. Type the standard "Hello, World" program shown below.
  15. Click File > New > File
  16. Call it Makefile
  17. Click Finish
  18. Create a Makefile similar to the one shown below. Again, we assume you are familiar with the structure of a Makefile. You cannot simply copy-and-paste this example because the gfortran and rm lines must start with a tab, not spaces. The -g switch instructs gfortran to include debugging symbols in the generated executable so that it can be debugged later. The -o switch tells it what to name the generated executable.
  19. Click Project > Clean, then click OK
  20. Open the Console view, and make sure "make" ran OK and compiled your program
  21. In the Fortran Projects view, expand the Binaries entry, and click on your executable (e.g., "hello.exe - [x86le]")
  22. Click Run > Run As > Local Fortran Application
  23. Choose GDB Debugger (Cygwin GDB Debugger if you're under Windows)
  24. Check the Console view, and make sure "Hello World" appeared.


program hello
    print *, "Hello World"
end program

Makefile: (You MUST replace the spaces in the gfortran and rm lines with a tab character!)

        gfortran -o hello.exe -g hello.f90

        rm -f hello.exe

Writing Code

The Fortran Perspective

If you are not already familiar with opening other views in your current perspective, you will find the following list from the Eclipse help guide helpful.

Selecting / Opening Views:

  • You can add views to a perspective. From the menu bar choose Window > Show View > Other and select a new view from the Show View dialog.
  • To reset the current perspective to its original layout, from the menu bar choose Window > Reset Perspective.

Fortran Perspective By default, the Fortran perspective contains an editor and the following views:

  • Project Explorer
  • Navigator
  • Console
  • Problems
  • Fortran Declaration
  • Outline Make Targets

Debug Perspective The debug perspective contains an editor area and the following views:

  • Debug
  • Variables
  • Breakpoints
  • Registers
  • Modules
  • Outline
  • Console
  • Tasks
  • Problems
  • Executables
  • Memory

The Fortran Projects View

The Fortran Projects view displays project files in a tree structure. In this view you can do the following:

  • Browse the elements of Fortran files
  • Open files in the editor view
  • Open projects in a new window
  • Create new projects, files, or folders
  • Manage existing files (cut, paste, delete, move or rename)
  • Import or Export files and projects

Files that you select in the Fortran Projects view affect the information that is displayed in other views.

The Fortran projects view is similar to the Projects View.

Using the Fortran editor and Fortran perspective

Selecting free vs. fixed form

Photran supports both fixed-form and free form Fortran code, each form having its own editor.

The free form Fortran editor allows the user to structure code as he/she wishes as long as it contains corrrect syntax.

Free Form Fortran Editor

The Fixed form Fortran reinforces the fixed-form Fortran syntax. If you are not familiar with the fixed form of Fortran programming, don't worry; Fixed form is more common in older Fortran programs, usually using Fortran-77 or earlier versions. Fixed form Fortran requires that all program statements are contained in columns 7 through 72. Anything after column 72 is ignored and anything before column 7 (except 'c', 'C', or '!' for comments) will result in a syntax error.

The Fixed form Fortran editor will notify you if your code is not correctly formatted. Opening free form code in the fixed-form editor will result in a watermark reading "Warning: Content Type Mismatch" being displayed in the upper right corner of the editor.

Fixed Form Fortran Editor

The free form editor is the default Fortran editor. If you wish to open fortran files in the fixed form editor, simply right-click the file in the project explorer > Open With > Fortran Editor (Fixed Form). To switch back to the free form editor, do the same, but select Fortran Editor (Free Form) instead.

Switching Editors

Outline view

The Outline view in the Fortran perspective shows an outline of the structural elements of a structured file currently open in the editor. The Outline view notes what type of Fortran source (free form or fixed form) is open in the current editor. It will also note when there is an error in the code.

Outline ViewOutline Error

To add the Outline view to the current perspective go to Window > Show View > Other... > General > Outline.

Overview of the Fortran editors

Both the free form and fixed form editors support the same features. The main features to note are the horizontal ruler at the top of the editor, code folding, and smart syntactic highlighting.

The horizontal ruler indicates the width of the actual page you would be typing on. It shows dash and plus (-/+) characters for each column in the editor. It is possible to turn on the print margin in the 80th column. This is discussed further below in the section titled "Configuring the Editor."

Editor Ruler

Code folding is supported by the Fortran editors, but it is disabled and the horizontal ruler is enabled by default. Turning code folding on in the Fortran preferences will disable the horizontal ruler (how to do this is described below as well) and cause programs, functions, and subroutines to fold similar to how Java and C/C++ methods, classes, etc. fold.

Editor Folding

The editors also support smart syntactic highlighting. As you write programs in Fortran, you will notice the different colors applied to Comments, Identifiers, Intrinsics, Keywords, and Strings to make code more readable. It is possible to change the colors for each of the previously mentioned code components in the Fortran editor preferences (this is discussed in the Configuring the Editor section).


To comment a statement, type an exclamation point (!) before the desired comment. Removing the exclamation point will uncomment the statement.

Unfortunately, block comments are not supported in Fortran. Block comments may be supported in later releases of Photran.

Setting bookmarks

Eclipse supports Bookmarks which can be set on files or on specific lines of files to remember important locations within files. To set a bookmark, right-click the grey bar on the left side of the editor at the line where the bookmark should be located and select "Add Bookmark..." from the popup menu. A bookmark can also be placed on a line by locating the cursor on the line, going to Edit > Add Bookmark... in the menu bar. Type in the desired name for the bookmark in the dialog box and click OK. A blue bookmark will show up in the grey bar on the left side of the editor.

Bookmarks can also be viewed in the Bookmarks view (Window > Show View > Other..., select Bookmarks in the General folder).

Go to line (Ctrl+L)

To navigate to a specific line of code in the editor, there are two ways to access the "Go To Line..." feature. Open the file to navigate and

while the editor window is active, in the menu bar, go to Navigate > Go To Line... or press Ctrl+L to open the Go To Line dialog box. Typing in the line you wish to navigate to and clicking OK will locate the cursor at the beginning of the specified line and jump to that location.

Configuring The Editor

Selecting horizontal ruler vs. folding

The horizontal ruler at the top of the editor is enabled by default. To enable code folding and disable the horizontal ruler, go to Window > Preferences in the menu bar. Expand Fortran and select Editor. Check the appropriate box(es) to enable folding in the free-form and/or fixed form Fortran editor.

Setting Colors for syntax highlighting

The colors for Fortran syntax highlighting can be modified in the Fortran editor preferences. To modify the color settings, go to Window > Preferences in the menu bar. Expand Fortran and select Editor. The color choosers for Comments, Identifiers, Intrinsics, Keywords, and Strings are available on this page.

Showing Print Margin

To enable display of the print margin (column 80 in the editor) go to Window > Preferences in the menu bar. Under General, expand Editors, and select Text Editors. Check the box for "Show print margin". Click Apply and the print margin should now display in the editor.

Converting Tabs to spaces

To enable conversion of Tabs to spaces, go to Window > Preferences in the menu bar. Under General, expand Editors, and select Text Editors. Check the box for "Insert spaces for tabs" to have Eclipse automatically convert Tabs to spaces.

Show whitespace

Whitespace characters can be displayed by going to Window > Preferences. Under General > Editors > Text Editors, check the box next to "Show whitespace characters" and click Apply. Whitespace characters will now show up in the editor as grey dots.

Set Font

Changing font in the Fortran editor is currently not supported.

Show line numbers

Line numbers can be displayed in the editor in the Text Editor preferences page. Go to Window > Preferences. Under General > Editors > Text Editors, check the box "Show line numbers" and click Apply.

Compiling Fortran Programs

Photran allows you to build projects with automatically generated Makefiles as well as custom makefiles, which allow the use of compilers other than gFortran which is Photran's default Fortran compiler. Photran also comes packaged with support for Intel's Fortran compiler and IBM's XLF compiler.

When you create a new Fortran project, you will be asked to name your project as well as choose a type and toolchain.

  • To use an automatically generated makefile, choose "Executable (Gnu Fortran)" from the Project type menu. Yo may need to uncheck the box below reading "Show project types and toolchains if they are supported on the platform" in order to be able to select the GCC toolchain in the toolchain selection box.
  • To create a project using your own custom makefile, in the project type selection box, expand the Makefile Project folder, and select Empty Project. Name the project and select the toolchain of your choise (For example, Windows users will likely choose Cygwin GCC).
Choosing a Fortran project type


Building Fortran projects is very similar to Building C/C++ Projects.

Check out the Documentation to find out more about the required tools and other information (like Makefiles and build settings) about building projects.

Setting make targets

Setting make targets for Fortran programs is the same as make targets with CDT. Refer to the previous link for an easy guide to creating make targets and more information on creating make targets.

Error parser

In order to get feedback about any errors in your Fortran programs, you will need to have some Error parsers selected in your Fortran project's build settings. To modify these settings, right-click on your Fortran project, go to Properties > Fortran Build > Settings and select the Error Parsers tab. A list of error parsers available to you is displayed.

You will notice that most of the default error parsers are the CDT parsers, which is partly why Photran requires CDT to be installed in your Eclipse environment. Select the error parser(s) you wish to use (usually depending on which compiler you are using) and click Apply and/or OK.

Fortran Error Parsers

Binary parsers - need to change if no "Run as Local Fortran App" menu item

In order to actually be able to compile and run your Fortran application, you will need to tell Eclipse which Binary Parser(s) to use for your project. This can be done in the project properties (Right-click project > Properties > Fortran Build > Settings > Binary Parsers Tab).

Which binary parser you want to use will depend on the operating system environment you are working in. For example, the default choice is the Elf Parser which is for Linux environments. Windows users would need to deselect the Elf Parser and select the PE Windows Parser and/or the Cygwin PE Parser.

Fortran Binary Parsers
Run as Local Fortran Application

Running and Debugging Fortran Programs

If you want to simply run a Fortran application, you can right-click the project in the project explorer > Run As > Local Fortran Application. This will build and run the Fortran application and output will be printed to the console. Note: If you are using a custom makefile, the makefile will need to be written correctly so the project can be built.

If you want to manage the run configuration, such as adding arguments or environment variables, Right-click your project in the explorer > Run As > Run Configurations... Create a new launch configuration under Fortran Local Application and modify the settings as needed to meet your run configuration specification.

Debugging programs works similarly, except Right-Click your project > Debug As > Local Fortran Application or Debug Configurations. Note that if you create a new Run/Debug configuration for your project, there is a Debug tab where you can choose the debugger you wish to use. GDB is the default debugger used by Photran.


Running and Debugging Fortran applications is similar to running and debugging C/C++ applications.

Refer to the documentation for a more detailed guide to run/debug configurations.

Setting breakpoints

There are two ways to set breakpoints in the editor view.

The easiest way to set a breakpoint in the editor is to double click in the left margin (gray vertical bar) on the line at which you wish to set the breakpoint. A blue dot will appear in the margin on the line where the breakpoint is set. Double clicking again at the same location will remove the breakpoint.

You can also set a breakpoint by right-clicking in the left margin on the line where you wish to set the breakpoint and clicking "Toggle Breakpoint." The blue dot indicating the breakpoint will appear or disappear (if already set) in the left margin of the editor.

Setting Breakpoints

Known Run/Debug Issues

When using Cygwin in Windows, Debugging a program can result in a "cannot find gcc source" error as described in 280492. Note that this error does not have an effect on the running of the program. The program will still run correctly in Debug mode.

Compiler-specific problems


In debug mode, using the step button to step through the code line-by-line sometimes jumps ("leapfrog" effect) around in the source code editor view. For example, pressing F6 (step) after a breakpoint several times, might sometimes result in a jump to line 1 and stepping again will return to the correct line in the code.


No known issues.

Intel Fortran Compiler

No known issues.


No known issues.

Advanced Features

Photran 5.0 includes a number of sophisticated features that are designed to make it easier to write, modify, search, and maintain Fortran code. These include content assist, which can "auto-complete" variable and function names as you type; a declaration view, which can show the leading comments for the selected variable or procedure; Fortran Search, which allows you to find declarations and references to modules, variables, procedures, etc.; and refactorings, which change your source code to improve its design while preserving its behavior.
Documentation for Photran's advanced features is available here.


If you are experiencing troubles with installing or working with Photran, you might want to check out our FAQ[10]

And if you don't find your answer there, feel free to e-mail them to our Mailing List[11]

Beyond Photran


  • Using Photran with other Eclipse plug-ins
    • Subversion support
    • PTP/RDT
    • RSE