Getting started with C on my Linux machine.

[ThaDoctor]

I would like to get started with programming in C, but I cant get it to
work, I do not need any compiler or such.
Only a basic explanation of the first program Hello World that print
"Hello World" on the screen.

Greetings Tobias

[spibou]

me********@aol. com wrote:

Chris Dollin wrote:

ThaDoctor wrote:

>
pete skrev:
>
>ThaDoctor wrote:
>
I would like to get started with programming in C,
but I cant get it to
work, I do not need any compiler or such.
Only a basic explanation of the first program Hello World that print
"Hello World" on the screen.
>>
>The whole point of the Hello World program,
>is to gain enough familiarity with your C implementation
>to write, translate, and execute a C program.
>>
>--
>pete
>
And after this how do I run the program under linux ?

The same way you run any other program in Linux, which, if
you ran the compiler, you presumably already know.

How does it follow from running the compiler by invoking
"gcc hello.c" that one runs the program by typing "./a.out"?

umteenth_out_of _topic_post {

Because the compiler as a default will create an executable
with name a.out (derived from "assembler output") in your
working directory. In Unix a single dot (.) is shorthand for
your working directory. So typing "./a.out" (without the quotes)
tells to the operating system to execute the file in the working
directory with name a.out Of course such a file will be created
only if the compilation completed without poblems.

If dot (.) appears in your PATH variable then you can simply type
a.out If you didn't understand the last sentence you can safely
ignore it.
}

Christopher Benson-Manica wrote:

ThaDoctor <To*********@gm ail.comwrote:

and after I have written and cmpiled how do I run the program under
linux ?

<ot>
Run a.out. man gcc for details, assuming that's your compiler.
Take further questions to comp.unix.progr ammer.
</ot>

I don't think that a beginner will get much out of the gcc man page.
Bill Pursell wrote:

ThaDoctor wrote:

pete skrev:

ThaDoctor wrote:
I would like to get started with programming in C,
but I cant get it to
work, I do not need any compiler or such.
Only a basic explanation of the first program Hello World that print
"Hello World" on the screen.
>
The whole point of the Hello World program,
is to gain enough familiarity with your C implementation
to write, translate, and execute a C program.

and after I have written and cmpiled how do I run the program under
linux ?

% gcc hello_world.c -o hi # compile the program
% ./hi # execute the program

There is a pitfall here in that if there's already a file with name
"hi",
then the compilation command will silently overwrite it.

Spiros Bousbouras

[mensanator]

sp****@gmail.co m wrote:

me********@aol. com wrote:

Chris Dollin wrote:

ThaDoctor wrote:
>

pete skrev:

ThaDoctor wrote:

I would like to get started with programming in C,
but I cant get it to
work, I do not need any compiler or such.
Only a basic explanation of the first program Hello World that print
"Hello World" on the screen.
>
The whole point of the Hello World program,
is to gain enough familiarity with your C implementation
to write, translate, and execute a C program.
>
--
pete

And after this how do I run the program under linux ?
>
The same way you run any other program in Linux, which, if
you ran the compiler, you presumably already know.

How does it follow from running the compiler by invoking
"gcc hello.c" that one runs the program by typing "./a.out"?

umteenth_out_of _topic_post {

Because the compiler as a default will create an executable
with name a.out

But because it is a default, there is no reason to assume that
a new user would know that. If the syntax of the compiler forced
you to specify a destination file, such as "gcc hello.c a.out",
then it would follow that the user would know what the output
file is because he had to type it. When defaults are involved,
it does not follow that a user knows how to run the program
since he knew how to run the compiler.

(derived from "assembler output") in your
working directory. In Unix a single dot (.) is shorthand for
your working directory. So typing "./a.out" (without the quotes)
tells to the operating system to execute the file in the working
directory with name a.out

That wasn't what I was asking. I asked how does knowing how
to run the compiler without the leading "./" infer that one must
preceed a.out with "./"?

Of course such a file will be created
only if the compilation completed without poblems.

If dot (.) appears in your PATH variable then you can simply type
a.out If you didn't understand the last sentence you can safely
ignore it.
}

Christopher Benson-Manica wrote:

ThaDoctor <To*********@gm ail.comwrote:

and after I have written and cmpiled how do I run the program under
linux ?

<ot>
Run a.out. man gcc for details, assuming that's your compiler.
Take further questions to comp.unix.progr ammer.
</ot>

I don't think that a beginner will get much out of the gcc man page.
Bill Pursell wrote:

ThaDoctor wrote:

pete skrev:
>
ThaDoctor wrote:
I would like to get started with programming in C,
but I cant get it to
work, I do not need any compiler or such.
Only a basic explanation of the first program Hello World that print
"Hello World" on the screen.

The whole point of the Hello World program,
is to gain enough familiarity with your C implementation
to write, translate, and execute a C program.
>
and after I have written and cmpiled how do I run the program under
linux ?

% gcc hello_world.c -o hi # compile the program
% ./hi # execute the program

There is a pitfall here in that if there's already a file with name
"hi",
then the compilation command will silently overwrite it.

Spiros Bousbouras

[Clifford Stern]

On 27 Jul 2006 10:29:04 -0700, "me********@aol .com" <me********@aol .com>
wrote:

>That wasn't what I was asking. I asked how does knowing how
to run the compiler without the leading "./" infer that one must
preceed a.out with "./"?

This isn't a compiler issue, it's a matter of whether the current
directory is in the PATH variable. When I want a program to execute
without the leading "./", I move it to /usr/local/bin.

Clifford Stern
ax***@lafn.org

[mensanator]

Clifford Stern wrote:

On 27 Jul 2006 10:29:04 -0700, "me********@aol .com" <me********@aol .com>
wrote:

That wasn't what I was asking. I asked how does knowing how
to run the compiler without the leading "./" infer that one must
preceed a.out with "./"?

This isn't a compiler issue,

I didn't say it was.

it's a matter of whether the current
directory is in the PATH variable.

I didn't ask why it works the way it does.

When I want a program to execute
without the leading "./", I move it to /usr/local/bin.

No one asked what you want. The question was

"How does knowing how to run the compiler infer that
one knows how to run the program?"

Please try to keep up.

>
Clifford Stern
ax***@lafn.org