Hi...
I'm new to linux and g++, and I'm writing here out of frustration when even simple things don't seem to work...

I'm trying to compile a small little test program that looks as follows:

#include <stdlib.h>
#include <stdio.h>
#include <gsl/gsl_sf_bessel.h>

int main(){

printf("%.22f\n", gsl_sf_bessel_J0(1.0));

return (0);

}

I have built and installed the GSL library in my home directory (instead of the default usr/local). libgsl.a is in myhomedir/lib and all header files are in myhomedir/include/gsl, including gsl_sf_bessel.h which I try to use.

I now try to compile program using a simple Makefile:
test: test.o

g++ test.cpp -I/user/myhomedir/include -L/user/myhomedir/lib libgsl.a -o test

when calling make, I keep getting the gsl/gsl_sf_bessel.h: No such file or directory ?????

What am I doing wrong?

Also, I wonder why make does not return any errors when I put a phony directory in, such as -I/phony/phony ?

Thanks for helping out!

Niko

Check for a mispelling, and check that the file actually exists. It should work whether you use angle brackets or double quotes.

I created an include directory in my home directory and moved a header file there. Adding the include directory argument for the command it worked as expected using first angle brackets and then double quotes.

Hi jschiwal,
I tried that, but keep getting the message. Furthermore, the -I/user/myhomedir/include option should instruct the compiler/linker of the locations to search.

When I type at the command prompt:
g++ -I/user/myhomedir/include -v test.cpp

I get the following (partial output) which indicates that the -I option has been set:
...
#include <...> search starts here:
/user/myhomedir/include
/usr/include/c++/3.2.3
...

That's why I don't understand why I keep getting the message!

Niko

My post mentioned that both ways should work, so cd to the gsl directory and make sure that that include file exists. Also check the permissions. Make sure the directory and the file are readable.

Hmm...jschiwal
You edited your first message, because it didn't first say that both should work... Is that good practice? Anyway...

Yes I checked that the file exists, is in the correct location, and is editable. These files are in my home directory.

Thanks

Niko

Hi -

I'm wondering if maybe the problem is coming from "make" (and not, as we've been assuming, from the g++ compiler).

Suggestion:
Try compiling from the command prompt (you said you tried "-v", but you didn't say whether or not you actually tried a command-line compiler, or whether or not it worked).

Just a thought...

Yes, I edited it just after posting it the first time. Sorry for the confusion.

If this command gives you that error, then the problem isn't due to make because make isn't used. The verbose command might give more information, but taking the error message at its word and checking the file it is complaining about seems like the best bet.