basic usage questions


I’m trying to use the PGroup debugger to step through a horrible mess of legacy spaghetti F77 code, in hopes of porting it to linux. The code dies after trying to read the 6th line of input. The debugger hangs at line 31 of the “Disassembly”. I confess to never having used a debugger before.

The code expects to find several files in the directory of execution and it needs input on stdin. If I execute “pgdbg (path to executable)” should the executable be able to find the files it needs? Further, entering a “run < input” command in the debugger should feed the contents of “input” to the program on stdin, correct? This doesn’t seem to be working. Does it need the absolute path to “input”.

The debugger hangs right at the point where it tries to read input from unit 5. Any suggestions?


It sounds like you are doing the right things. Invoke the debugger as follows (’$’ is the prompt):

$ pgdbg your_app

Then to run it with redirection from stdin, use the following command (‘pgdbg>’ is the prompt):

pgdbg> run < your_input_file

A relative path to your_input_file should work fine. If you are having trouble with this and just want to make progress, you could try the following:

(1) invoke your program using the ‘run’ command without input redirection
(2) copy and paste the first dozen or so lines of your input file into the Program I/O Window. Your program should read it from that window as though you typed it in.

I suggest this since you say the program is hanging on line six of the input. Obviously this workaround isn’t useful if you have thousands of lines of input, but you should be able to get at your particular problem this way.

If you run into more problems with this please let us know.

Hmm. Weird. I still can’t get this to work. Your other suggestion about pasting the input into the IO window works, though, and the input file is small (~15 lines). Thanks!

Please let us know the following information, by either posting here or sending email to

(1) which version of the debugger you are using (run ‘pgdbg -V’ to get this information)

(2) what operating system you are running on

(3) what version of the operating system it is

and we will look into the problem further.

Glad to hear the workaround helped, at least.