The title says it all really, I run gfortran to compile a simple test fortran program, it compiles with no errors; but when I run ls to look at the output, there is no executable created. I've tried with the -o option set as well.
The fotran program is a simple hello world
program test1
implicit none
print *, "Hello World!"
end program test1
(The gfortran I'm using is from the mingw release; I have aliased gfortran to c:/mingw/bin/gfortran.exe within powershell, but the same problem happens if I call it explicitly)
Has anyone had this problem before? I thought it might be a permissions issue but I can create files from powershell just fine (unless gfortran needs additional permissions for some reason?). Any help greatly appreciated, thanks :)
Turns out simply aliasing the path to the compiler doesn't work in powershell for MinGW, adding the mingw bin directory to the path is necessary and solved my problem as #cup suggested in the comments. Thanks everyone :)
I just happened to have the same problem that you described but two years later ...
I found that I just need to call the program as ./test.exe instead of test.exe, as I would have done with MS-DOS. That way I do not have to change the path if I work in a different folder.
Just finished installing the compiler gfortran 6.1. El Capitan. Next, I want to know how to run a file. So, I have a few questions:
Which extension should I use to save the file? Is it .f90 or something else?
What kind of software can be used to edit and save the source code?
Once I save the file, how do I compile it? Is is gfortran followed by the file name (with path) in the Terminal? Also, how does the path look like on a Mac?
A step by step guide would be a great help. I am a first time Mac user. :)
.f90 for free formatted sources is commonly used
Any texteditor you are comfortable with and used to, vim for example
gfortran /your/source/file that would be with an absolute path. If you are in the directory of the source file already you do not need to specify the complete path.
Step by step "hello world":
Create a text file with your Fortran program
Just to give a command line example without the need for an editor (this is not what you typically would do):
Open the terminal, then enter
cat >hello.f90 <<EOF
program hello
implicit none
write(*,*) 'hello world'
end program hello
EOF
Compile your program in the terminal with: gfortran hello.f90
Execute it in the terminal with ./a.out
If you want another name use the -o option:
gfortran -o hello hello.f90
./hello
This feels like a silly question, but my touch command seems to have broken. Trying to create the ~/.bash_profile file using the command: touch ~/.bash_profile and seeing the following when I send the command: -bash: touch: No such file or directory. I've search quite a bit for an answer but haven't found the same problem so far. Can anyone assist? What exactly do I need to do in order to make the touch command work?
You might like to run the touch command through OS X's equivalent of strace (I think that command exists on OS X, actually, although there appear to be others), go through the output and examine what errors are generated, if any. Pasting the output to a pastebin may also be a good idea.
I think this is one of those instances where the call to strerror() inside touch's C code is referencing an insane value of errno. (This is where all those "Error performing <X>: Success" messages come from. There was an error, but errno subsequently got set to 0 by a successful command before errno was captured and the error message printed.)
I have OS X Mavericks, and I use Kornshell, but I'll switch over to bash:
Let's try touching a non-existent file:
$ touch foo
Nope. That worked. Let's try touching a file you don't own:
$ touch /usr/bin/true
touch true: Permission denied
Nope, that's what I expected and not what the OP got. Let's try with a symbolic link
ln -s foo bar
touch bar
Nope, worked. Let's try it with a directory:
$ touch Applications
Nope, also worked.
Try this:
$ sum /usr/bin/touch
6205 9 /usr/bin/touch
$ file /usr/bin/touch
/usr/bin/touch: Mach-O 64-bit executable x86_64
If you're using Mavericks, I assume you should get the same results.
How can I compile/run C or C++ code in a Unix console or a Mac terminal?
If it is a simple single-source program,
make foo
where the source file is foo.c, foo.cpp, etc., you don’t even need a makefile. Make has enough built-in rules to build your source file into an executable of the same name, minus the extension.
Running the executable just built is the same as running any program - but you will most often need to specify the path to the executable as the shell will only search what is in $PATH to find executables, and most often that does not include the current directory (.).
So to run the built executable foo:
./foo
gcc main.cpp -o main.out
./main.out
This is the command that works on all Unix machines... I use it on Linux/Ubuntu, but it works in OS X as well. Type the following command in Terminal.app.
g++ -o lab21 iterative.cpp
-o is the letter O, not zero
lab21 will be your executable file
iterative.cpp is your C++ file
After you run that command, type the following in the terminal to run your program:
./lab21
Two steps for me:
First:
make foo
Then:
./foo
All application execution in a Unix (Linux, Mac OS X, AIX, etc.) environment depends on the executable search path.
You can display this path in the terminal with this command:
echo $PATH
On Mac OS X (by default) this will display the following colon separated search path:
/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin
So any executable in the listed directories can by run just by typing in their name. For example:
cat mytextfile.txt
This runs /bin/cat and displays mytextfile.txt to the terminal.
To run any other command that is not in the executable search path requires that you qualify the path to the executable. So say I had an executable called MyProgram in my home directory on Mac OS X I can fully qualify it like so:
/Users/oliver/MyProgram
If you are in a location that is near the program you wished to execute you can qualify the name with a partial path. For example, if MyProgram was in the directory /Users/oliver/MyProject I and I was in my home directory I can qualify the executable name like this, and have it execute:
MyProject/MyProgram
Or say I was in the directory /Users/oliver/MyProject2 and I wanted to execute /Users/oliver/MyProject/MyProgram I can use a relative path like this, to execute it:
../MyProject/MyProgram
Similarly if I am in the same directory as MyProgram I need to use a "current directory" relative path. The current directory you are in is the period character followed by a slash. For example:
./MyProgram
To determine which directory you are currently in use the pwd command.
If you are commonly putting programs in a place on your hard disk that you wish to run without having to qualify their names. For example, if you have a "bin" directory in your home directory for regularly used shell scripts of other programs it may be wise to alter your executable search path.
This can be does easily by either creating or editing the existing .bash_profile file in your home directory and adding the lines:
#!/bin/sh
export PATH=$PATH:~/bin
Here the tilde (~) character is being used as a shortcut for /Users/oliver. Also note that the hash bang (#!) line needs to be the first line of the file (if it doesn't already exist). Note also that this technique requires that your login shell be bash (the default on Mac OS X and most Linux distributions). Also note that if you want your programs installed in ~/bin to be used in preference to system executables your should reorder the export statement as follows:
export PATH=~/bin:$PATH
Do all of this in "Terminal".
To use the G++ compiler, you need to do this:
Navigate to the directory in which you stored the *.cpp file.
cd ~/programs/myprograms/
(the ~ is a shortcut for your home, i.e. /Users/Ryan/programs/myprograms/, replace with the location you actually used.)
Compile it
g++ input.cpp -o output.bin (output.bin can be anything with any extension, really. Extension .bin is just common on Unix.)
There should be nothing returned if it was successful, and that is okay. Generally you get returns on failures.
However, if you type ls, you will see the list of files in the same directory. For example, you would see the other folders, input.cpp and output.bin
From inside the directory, now execute it with ./outbut.bin
A compact way to go about doing that could be:
make foo && ./$_
It is nice to have a one-liner so you can just rerun your executable again easily.
Assuming the current directory is not in the path, the syntax is ./[name of the program].
For example ./a.out
To compile C or C++ programs, there is a common command:
make filename
./filename
make will build your source file into an executable file with the same name. But if you want to use the standard way, You could use the gcc compiler to build C programs and g++ for C++.
For C:
gcc filename.c
./a.out
For C++:
g++ filename.cpp
./a.out
Add the following to get the best warnings, and you will not regret it. If you can, compile using WISE (warning is error).
- Wall -pedantic -Weffc++ -Werror
Step 1 - create a cpp file using the command
touch test.cpp
Step 2 - Run this command
g++ test.cpp
Step 3 - Run your cpp file
./a.out
I am on a new MacBook Pro with the Apple M1 Pro chip. I have my Xcode installed - both IDE and command line tools. This is how it worked for me:
g++ one.cpp -o one
./one
Use a makefile. Even for very small (= one-file) projects, the effort is probably worth it because you can have several sets of compiler settings to test things. Debugging and deployment works much easier this way.
Read the make manual. It seems quite long at first glance, but most sections you can just skim over. All in all, it took me a few hours and made me much more productive.
I found this link with directions:
http://www.wesg.ca/2007/11/how-to-write-and-compile-c-programs-on-mac-os-x/
Basically you do:
gcc hello.c
./a.out (or with the output file of the first command)
In order to compile and run C++ source code from a Mac terminal, one needs to do the following:
If the path of .cpp file is somePath/fileName.cpp, first go the directory with path somePath
To compile fileName.cpp, type c++ fileName.cpp -o fileName
To run the program, type ./fileName
Just enter in the directory in which your .c/.cpp file is.
For compiling and running C code.
gcc filename.c
./a.out filename.c
For compiling and running C++ code.
g++ filename.cpp
./a.out filename.cpp
You need to go into the folder where you have saved your file.
To compile the code: gcc fileName
You can also use the g++ fileName
This will compile your code and create a binary.
Now look for the binary in the same folder and run it.
For running C++ files, run the below command, assuming the file name is "main.cpp".
Compile to make an object file from C++ file.
g++ -c main.cpp -o main.o
Since #include <conio.h> is not supported on macOS, we should use its alternative which is supported on Mac. That is #include <curses.h>. Now the object file needs to be converted to an executable file. To use file curses.h, we have to use library -lcurses.
g++ -o main main.o -lcurses
Now run the executable.
./main
Running a .C file using the terminal is a two-step process.
The first step is to type gcc in the terminal and drop the .C file to the terminal, and then press Enter:
gcc /Desktop/test.c
In the second step, run the following command:
~/a.out
I'm looking for a way to programatically set the 'executable' bit on a file on OS X. I don't want to invoke 'chmod a+x' but I want the same effect as the chmod call. Any suggestions? A carbon API or any other C/C++ function would work...
See chmod(2), e.g. http://www.manpagez.com/man/2/chmod/osx-10.4.php (I think it's unchanged in 10.5).
There is a "chmod" C library call. Go to a terminal window and type "man 2 chmod".