How to 'delete' and 'echo' in Linux??

[goodboy]

Dear all,
this is my first time I post in the forum.

I would like to ask you if you know how I can get my hostname and how I can use echo in linux using C.
I dont want the system() or execl ways, I want to make the code!

Can anyone help me?

Thanks!

[claudiu]

Welcome to the forum!

What exactly do you mean by "I want to make the code"? Give an example of how you would want to run this program of yours to clarify things.

[jeffcobb]

Look for unlink() for deleting a file...hostname is done via the BSD socket libs, gethostbyname() I think (gotta look it up, been a while since I used it). Echo is accomplished by basic C IO commands (some echo the input, others do not). Now if you meant by echo 'print stuff to screen), printf() will work fine, is basic C and not unique to Linux..

[cpjust]

Look for unlink() for deleting a file

Why not remove() which is a standard C function, instead of using a platform specific function?

[goodboy]

Thanks!
for example I have tried the code below to get the current directory:

#define FALSE 0
#define TRUE !FALSE

extern int alphasort();

char pathname[MAXPATHLEN];

main() {
    int count, i;
    struct direct **files;
    int file_select();

    getwd(pathname);
        
        
    printf("Current Working Directory = %s\n", pathname);
    count = scandir(pathname, &files, file_select, alphasort);

    /* If no files found, make a non-selectable menu item */

 }

int file_select(struct direct *entry)
 {
    if ((strcmp(entry->d_name, ".") == 0) ||
            (strcmp(entry->d_name, "..") == 0))
        return (FALSE);
    else
        return (TRUE);
}

it works without any problem.
So I'm looking to do something same with "echo" and "rm"...
Any ideas??

[MK27]

echo this would be

#include <stdio.c>
printf("%s","this");

rm that.file would be

#include <unistd.h>
unlink("that.file");

[itCbitC]

Are you trying to write a C program that does what the "echo" utility does on *nix systems?

[goodboy]

Thanks for your reply!

rm works OK!!!
but I have problem with "echo"
I wrote this:

#include <stdio.h>
main()
{
printf("%s","this");
}

then I wrote in terminal "./a.out blabla" and I didnt see my message :-(

....

[MK27]

Ah -- you need to use the command line args:

int main(int argc, char *argv[]) {
    if (argc < 2) {
        puts("echo what?!");
        return -1;
    }
    printf("%s\n",argv[1]);
    return 0;
}

[claudiu]

Just curious but why are you reinventing the wheel with these functions?

[jeffcobb]

Why not remove() which is a standard C function, instead of using a platform specific function?

Maybe because....the OP asked for a Linux way of doing it?

[cpjust]

Maybe because....the OP asked for a Linux way of doing it?

remove() works on Linux just the same as it does on any other OS. I only use platform specific code if there isn't a portable function available to do the job.

[goodboy]

Thanks for your reply guys!
Sorry for the delay but I didnt have internet connection.
OK so I have created 2 files...how I can write a C file and then call the mains of the other 2 files from my basic c file?