the hello program in KDevelop

boxerboy · 08-22-2005, 02:45 PM

hi im just starting to learn programming and already have problems i wrote the hello program in KDelop and when i was done i opened the konsole at bottom and logged in as root and typed "cc hello.c" as far as i know it was supposed to make a exe file called a.out so i went back to kopnsole and typed "a.out" as root and it gave me

/usr/lib/gcc/i386-redhat-linux/4.0.1/../../../crt1.o(.text+0x18): In function `_start':
: undefined reference to `main'
collect2: ld returned 1 exit status

not sure what that means but i looked over everything and its just as book has it i even indented the "printf" part.

boxerboy · 08-22-2005, 03:37 PM

oh and if theres a better or more beginner friendly program to use for "C" plz let me know ty. im using FC4 just incase u need that

exvor · 08-22-2005, 03:38 PM

Posting your source here would be helpfull.

Note as well you can compile programs without being root.

as a user try and compile it as such type only whats in red.

User@Nightmare$ gcc -Wall -o test hello.c

and post any erros you get.

boxerboy · 08-22-2005, 03:43 PM

Code:

#include <stdio.h>
main()
{
          printf("hello, john\n");
}

that is program as written now here is the errors after "gcc -wall -o test hell.c"

Code:

[boxerboy@localhost ~]$ gcc -Wall -o test hello.c
hello.c:3: warning: return type defaults to ‘int’
hello.c: In function ‘main’:
hello.c:5: warning: control reaches end of non-void function
hello.c:5:2: warning: no newline at end of file

devscott · 08-22-2005, 03:48 PM

main should return an int to tell the OS how it terminated.

so try this

#include <stdio.h>
int main()
{
printf ("Hello Linux Questions people");
return 0;
}

boxerboy · 08-22-2005, 03:55 PM

after trying devs version (pasted it in) i returned this:

Code:

[boxerboy@localhost ~]$ gcc -Wall -o test hello.c
/usr/lib/gcc/i386-redhat-linux/4.0.1/../../../crt1.o(.text+0x18): In function `_start':
: undefined reference to `main'
collect2: ld returned 1 exit status

looks like same thing only now its minus one error.

devscott · 08-22-2005, 04:06 PM

try doing just a

gcc -c hello.c

should compile fine...

Oh and you asked about programs... download install anjuta by

yum install anjuta

boxerboy · 08-22-2005, 04:11 PM

ok i tryed "gcc -c hello.c" and command line came up for me other than that no errors or nothing.
"a.out" is saying command not found.

devscott · 08-22-2005, 04:19 PM

yeah in never built that file. but we know it compiled successfully

try this

gcc hello.c -o hello

and then run it
./hello

should give you your desired results.

boxerboy · 08-22-2005, 04:39 PM

Quote:

Originally posted by devscott
try doing just a

gcc -c hello.c

should compile fine...

Oh and you asked about programs... download install anjuta by

yum install anjuta

i installed it and it said it installed succesfully but i dont see it in the list under programming. is it called that or would it store it under different name?

boxerboy · 08-22-2005, 04:43 PM

ok heres what happened using KDevelop

Code:

boxerboy@localhost ~]$ gcc hello.c -o hello
/usr/lib/gcc/i386-redhat-linux/4.0.1/../../../crt1.o(.text+0x18): In function `_start':
: undefined reference to `main'
collect2: ld returned 1 exit status

boxerboy · 08-22-2005, 04:45 PM

ok i saved it this time lol i forgot to last time heres what i got

Code:

[boxerboy@localhost ~]$ gcc hello.c -o hello
hello.c:6:2: warning: no newline at end of file

boxerboy · 08-22-2005, 04:48 PM

i typed "./hello" and it worked i thinklol it said "hello boxerboy" and right after it gave my username$ i assuming thats it

devscott · 08-22-2005, 04:49 PM

typing anjuta

from the command line should start up anjuta

In gnome and FC I know you have to log out before a program is added, well at least on my system, to the menu. I don't know if KDE is the same.

as far as your error message... I don't know.

boxerboy · 08-22-2005, 04:57 PM

it worked i think thank you very much and i will try anjuta in a min. does "int" have to be in front of "main" always? and thank you again