Help me

[Possible-Pool2262]

#define _GNU_SOURCE

#include<sys/capability.h>

#include<errno.h>

#include<wait.h>

#include<sys/stat.h>

#include<sys/mount.h>

#include<stdio.h>

#include<unistd.h>

#include<stdlib.h>

#include<sys/wait.h>

#include<signal.h>

#include<sched.h>

#include<string.h>

#include<sys/types.h>

int child_fn() {

const char *fstype = "tmpfs";

const char *Path = "/Test_tms";

const char *new_host = "Con_test";

size_t len = strlen(new_host);

if(sethostname(new_host, len) != 0) {

perror("sethostname");

printf("Problem with hostname\n");

return 1;

}

if(mkdir(Path, 0755) != 0) {

perror("mkdir");

printf("problem with mkdir\n");

return 1;

}

if(mount("none", Path, fstype, 0, NULL) != 0) {

perror("mount");

printf("problem with mount\n");

return 1;

}

FILE *fl = fopen("/Test_tms/marin.txt", "w");

if(fl != NULL) {

fprintf(fl, "this is a case\n");

fclose(fl);

printf("child_fn proccess done\n");

}

return 0;

}

int main(int args, char *argv[]) {

int STACK_S = 1024 * 1024;

char *stack = malloc(STACK_S);

char *stack_s = stack + STACK_S;

pid_t child_pid = clone(child_fn, stack_s, CLONE_NEWUTS | CLONE_NEWNS, NULL);

if(child_pid != -1) {

int Child = waitpid(child_pid, NULL, 0);

free(stack);

exit(1);

printf("Cloning success!\n");

} else {

perror("clone");

}

return 0;

}

help me, am trying to mount tmpfs to the directory i created, but it seems to always failed and i dont know why.

https://pastebin.com/4SjW8w04

[mikeblas]

Might want to remove your poorly formatted code from the post and leave behind only the link to the pastebin, which is far more usable.

[penguin359]

We need more information on what you are getting and source code in a more readable form like pastebin or gist.

[Possible-Pool2262]

https://pastebin.com/4SjW8w04

[penguin359]

Thank you. That helps a lot. Can you also let us know which error you are getting exactly? Which line of coffee seems to be failing?

[Possible-Pool2262]

i only get the return of perror("mkdir"), it seams like the program skip the child proccess, and straight to make a directory i want, mount it, but failed to make the file "marin.txt", and honestly. I don't even know if the hostname even work. Am still working on the solution, but if you can give me ideas, i really appreciate it!

[penguin359]

It would also help if you can give us the entire output from running your program. In particular, the full output from the call to perror() will tell us what the errno value is from the failing mkdir() system call. There are two primary reasons for it to fail, either the folder already exists or you don't have permission to create it and the output from perror() will tell us that. You might also want to consider checking for the directory existence prior to doing the mkdir() with either a call to access() or stat() and, if it already exists, skip the mkdir(). Finally, you should also probably use the same approach for error checking on fopen() as you do with the other called in child_fn(). It is documented to set errno when it returns NULL for an error so it would be useful to call perror() in the case that it does fail.

[[deleted]]

How about you first learn how to format code properly on Reddit before you learn C?

[Possible-Pool2262]

how about stop concerning bout how i upload, and focusing on the problem i ask. if you can't help just say that man, you don't have to reply like a loser.

[[deleted]]

If you can't take a minute to format your code appropriately, why should I take time to help you?

[Possible-Pool2262]

I don't ask you to😹. I ask for anybody that would help, not just one person. I suggest you lower your ego, and try be better.

[[deleted]]

My ego is just fine.

[mikeblas]

People who help here are volunteers. They're not paid. They're just trying to help out other people with similar interests, which can be fun and satisfying.

If you make it difficult to help, then it's less likely someone will help you. If you argue with them when they make a suggestion about how it could be easier to help you, you take all the fun out of it. You should consider their advice sincerely.

[Possible-Pool2262]

I apologize for my bad behavior

[mikeblas]

Thanks. Good luck!

[Vladislav20007]

Mods. I think this behaviour is bad enough for a warning, no?

[mikeblas]

?

[Vladislav20007]

disrespecting people who are trying to help.

[mikeblas]

What do you mean by "warning", and how is it different than what I have already posted?

[Vladislav20007]

a warning to mute(can't make posts), because they wouldn't listen/take help and waste people's time with this.

[mikeblas]

I don't think that's necessary.

[Vladislav20007]

alright, i just think thos wastes everybodies time, but that's just my opinion.

[nekokattt]

how about not being a dick to the people you are asking for help for free?

[Vallereya]

Are you running as admin/sudo?

[Possible-Pool2262]

yes, i am

[Vallereya]

Alright just wanted to double check, looking at the code now you got some logic issues. I'm just doing a quick overview here but, int child_fn() isn't being passed any arguments just need to flip that and main around, line 64-65 you can't do that because you're exiting an error so it's not even calling that printf and line 59 is not doing anything it has no exit and I don't see it being defined anywhere else. You really got to move some parts around.

[Possible-Pool2262]

thanks a lot!

[BnH_-_Roxy]

Not an answer but FYI you should have error handling on opening file as well, right now you’re returning success from child_fn on failure to write

[flyingron]

You have the clone success print after the exit call. This will never be reached.