I have been trying to use Cygwin64 to compile and run C programs. I have been trying to run a simple Hello World program as follows:
#include <stdio.h>
int main()
{
printf("Hello world!");
}
And in Cygwin, I have been typing the following command:
gcc -o hello hello.c
Followed by
./hello.exe
After that, there is simply no output, and I receive a new prompt.
Does anyone have a solution to this issue?
Gcc don't give .exe extention for output executable file. You are giving gcc -o hello hello.c command then it generates executable with name hello (not hello.exe). If you don't give any name for output file, it generates executable file with name a.out
I would guess that the prompt printed after the execution of the program is printed by first returning the cursor to column 0. This is then overwriting the "Hello World!" message you've printed. You should probably add a "\r\n" to your printf call as follows:
#include <stdio.h>
int main()
{
printf("Hello world!\r\n");
}
This will move the cursor to the next line before exiting, so that the prompt is printed on the next line instead.
I guess you just need to pause your program.
Can be done with a get(), scanf()
Also you should do a return 0; at the end of your code
Related
I am incredibly new to the C language: I am trying to run sample C programs from codecademy, such as the hello world command below:
#include <stdio.h>
int main() {
// output a line
printf("Hello World!\n");
}
Bottom line is, every time I try to run any code in my macOS terminal, I always get the following error:
zsh: parse error near `\n'
What can I do to resolve this problem?
c is a language where you need to compile the code you've written. You do that by starting a C compiler and give the file containing your C code as input.
Example:
File: myfirstcprogram.c
#include <stdio.h>
int main(void) {
printf("Hello World!\n");
}
Then at the zsh prompt, invoke the compiler:
cc myfirstcprogram.c -o myfirstcprogram
-o myfirstcprogram is here an argument to the compiler telling it what to call the final program.
cc may be clang or gcc or any other compiler you've got installed if cc isn't already linked to the proper compiler.
When the compilation is done, the executable myfirstcprogram should have been created. You can now run it from your zsh prompt:
./myfirstcprogram
You can run it without recompiling it as many times as you like. Only when you change the source code (myfirstcprogram.c) do you need to compile the program into an executable again.
I'm new to coding and doing the first CS50 course exercise where we are taught to code using C and doing the "hello world" activity. I input the code:
#include <stdio.h>
int main(void)
{
printf("hello, world\n");
and when I type in the terminal make hello and ./hello it says hello is a directory instead of doing the command.
What should I do?
C is a compiled language, so once you compile the code, it will output an executable that unless specified by -o [executable-name], will be called a.out. Your hello world program should look like this:
#include <stdio.h>
int main() {
printf("hello, world\n");
}
Don't forget the closing bracket at the end. To compile this code, make sure you have GCC installed and run gcc [program-file-name].c, and replace the second argument with the name of the C file. Once the code is compiled, you can see that a file named a.out has appeared in your current directory. You can then run ./a.out to run the program.
I'm assuming your system comes with GCC, but if it doesn't, there are many resources on Google to help, including https://gcc.gnu.org/install/.
I wanted to run an Hello World program as I am starting in C :
#include <stdio.h>
int main(){
printf("Hello World\n");
return 0;
}
I compile it with this command : gcc h4.c -o h4
It create the executable h4 and when I click on it the command prompt pop and get shut down directly its like its running but to quick for me to see before it shut down.
use the command ./h4 in your command prompt to run the program but keep the prompt open.
Clicking on the executable also does "runs" the program, but it closes the window after the execution is finished.
Seems like you are on Windows. In this case, you don't need the prefix ./,just simply h4.exe. Or, if you really want to, you can use .\.
If you are not running it on your command prompt
do this:
#include <stdio.h>
#include <conio.h>
int main(){
printf("Hello world\n");
getch();
return 0;
}
Assuming your on windows, you should just type h4 instead if you want to run it on your command prompt.
I am using Windows 10 OS. I installed MinGW for compiling C programs. I tried running my program using the gcc command on the Command Prompt. The file compiles and an executable file(.exe) is formed in the same folder as my source file. But when I try running this file, I keep getting the message 'Access is denied'. Also the .exe file vanishes after this. I do not know what is wrong. Please help me out.
P.S Another time I did the same thing mentioned above and the .exe file ran and I was able to see the output on the Command line. And this time the .exe file did not vanish either.
What was the command you put to compile the program? Also to compile and make an executable file, you have to put this command - "gcc -o nameofexecutablefile nameofsourcefile.c", to run this program just type the name of your executable file in cmd. And to stop the program's window from closing, put "system("pause");" right before the "return 0;" in your program, at the end of the program it will display "Press any key to continue..." and when you press any key, the window will close. Also check if you did any mistakes in your program. I'll also give an example -
------------CODE-----------
#include <stdio.h>
#include <stdlib.h>
int main()
{
printf("Hello World\n");
system("pause"); // this will pause the window
return 0;
}
-------OUTPUT--------
Hello World
Press any key to continue...
I would like to make a script for testing my c program but I could not figure out why it does not work
I tested it with a easy code so that I am sure that the problem is not because of the C file.
My C Code is:
#include <stdio.h>
#include <stdlib.h>
int main()
{
printf("Hello World\n");
return 0;
}
And my Shell Script is:
gcc -o main main.c
echo "Hello world"
If I execute the script I get the error message on my console
: No such file or directory
gcc: fatal error: no input files
compilation terminated
This is the Error I get if I want to execute the script
https://imgur.com/a/zIl55
In the image you can see my problem
If I compile the C file “per hand” it has no problem but if I execute the script which contains the same statement it does not work.
If I just want to compile and only write the command for compiling in my script it works but as soon as I ad an echo or any other command it will not work.
I am using an Ubuntu Shell under Windows.
Any help would be very appreciated.
My guess: you wrote your script with a Windows-only editor such as Notepad, so it used Windows newlines (\r\n AKA CRLF). bash passes main.c\r as argument to gcc, which cannot find it. Printing out the error, the terminal interpret \r as carriage return character, so, it goes in column 1 and prints the rest of the message, which results in the bizarre thing you are seeing.
You can check if this is the case by running dos2unix over your script, if now it works correctly it's as I suspected.
Solution: use a more serious editor and/or make sure it writes Unix newlines (plain \n, AKA LF).