[SOLVED] C++ program compiled in Fedora 14 do not run

vonelli · 01-31-2011, 04:57 PM

I am very new in c programming. I could not get a simple compiled program to run, I am using Fedora 14. To learn the correct way I sign in to http://mrbook.org/tutorial/make/ and fallow the examples listed they all compile and generate the executable file but none run. To run them I try both way double chick the executable end on the command line but it does not do any thing. I will appreciate help, Vinny

schneidz · 01-31-2011, 05:22 PM

what is the program supposed to do ?
you can post source code.
usually this does it:

Code:

g++ hello.cpp -o hello.x
hello.x

Dark_Helmet · 01-31-2011, 05:26 PM

Quote:

Originally Posted by schneidz

usually this does it:

Code:

g++ hello.cpp -o hello.x
hello.x

Obligatory comment:
That only works if the current directory (".") is in your PATH. If typing "hello.x" gives a "command not found" error, then try:

Code:

./hello.x

Also, please post the contents of your Makefile. That will tell us the name of the program being created and what directory it is saved to.

EDIT:
The OP's link is incorrect. It gives a 404 error. I believe this is the correct link:
Mrbook's Tutorial on Makefiles

vonelli · 02-02-2011, 01:50 PM

Quote:

Originally Posted by Dark_Helmet

Obligatory comment:
That only works if the current directory (".") is in your PATH. If typing "hello.x" gives a "command not found" error, then try:

Code:

./hello.x

Also, please post the contents of your Makefile. That will tell us the name of the program being created and what directory it is saved to.

EDIT:
The OP's link is incorrect. It gives a 404 error. I believe this is the correct link:
Mrbook's Tutorial on Makefiles

-----------
I am not sure where to attach my reply, please correct me if I am using in wrong location.
sorry for wrong address, I try all the samples in that paper, here is one:

all: hello

hello: main.o factorial.o hello.o
g++ main.o factorial.o hello.o -o hello

main.o: main.cpp
g++ -c main.cpp

factorial.o: factorial.cpp
g++ -c factorial.cpp

hello.o: hello.cpp
g++ -c hello.cpp

clean:
rm -rf *o hello
This create hello executable file, but when I try to run it does not do any thing.

vonelli · 02-02-2011, 02:00 PM

I think that my reply may belong here.
-----------
I am not sure where to attach my reply, please correct me if I am using in wrong location.
sorry for wrong address, I try all the samples in that paper, here is one:

all: hello

hello: main.o factorial.o hello.o
g++ main.o factorial.o hello.o -o hello

main.o: main.cpp
g++ -c main.cpp

factorial.o: factorial.cpp
g++ -c factorial.cpp

hello.o: hello.cpp
g++ -c hello.cpp

clean:
rm -rf *o hello
This create hello executable file, but when I try to run it does not do any thing.

Dark_Helmet · 02-02-2011, 02:11 PM

Quote:

Originally Posted by vonelli

all: hello

hello: main.o factorial.o hello.o
g++ main.o factorial.o hello.o -o hello

If that is your Makefile, then open a terminal, cd to the directory with your Makefile, and type:

Code:

make
./hello

schneidz · 02-02-2011, 03:06 PM

Quote:

Originally Posted by vonelli

I think that my reply may belong here.
-----------
I am not sure where to attach my reply, please correct me if I am using in wrong location.
sorry for wrong address, I try all the samples in that paper, here is one:

all: hello

hello: main.o factorial.o hello.o
g++ main.o factorial.o hello.o -o hello

main.o: main.cpp
g++ -c main.cpp

factorial.o: factorial.cpp
g++ -c factorial.cpp

hello.o: hello.cpp
g++ -c hello.cpp

clean:
rm -rf *o hello
This create hello executable file, but when I try to run it does not do any thing.

is it not printing an error like 'command no found' ?
please post the contents of hello.cpp. i suspect that it doesnt have a printf/ cout so it looks like its not doing anything.

goodhombre · 02-02-2011, 04:29 PM

hi,

try this

Code:

chmod 755 ./hello.x
./hello.x

vonelli · 02-03-2011, 07:30 AM

Thank you very much, the ./hello works. Is possible of a quick explanation of why ./ is required?

goodhombre · 02-03-2011, 07:43 AM

Hi,

Linux shell forbids running of executables without explicit ./ if the executable is not located in one of the PATH directory.
See :

Code:

echo $PATH

This prevents running of executables you are not aware of, can be a malware , backdors , etc.

Also you have to make the file executable in order to be able to run it, this is what chmod +x did.
You can check if the file is executable by running :

Code:

ls -l ./hello.x

Check this link for more details about permissions.

vonelli · 02-03-2011, 12:15 PM

Thank you again, Vinny.