How to install nvidia-smi?

Question

I have been working on creating a C program that given a sequence of digits (provided as a char array), the program returns as many X as the number of digits the input contains (e.g. input: "1234"--> output:"XXXX")

The code I have written is:

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

const char* getPlaceholder(char * word);

int main(){

char * myWords []={"111","22222","1113445","9"};
char ** mywords_pointer=myWords;

/*We will apply the function getPlaceholder to each of the components of the myWords array */

for (int indx=0; indx<3; indx++){
char *currentWord=*(mywords_pointer+indx);
const char *placeholder;
printf("Calling function\n");
placeholder=getPlaceholder(currentWord);
printf("The placeholder for %s is: %s\n",currentWord, placeholder);

}
return 0;
}


//getPlaceholder gets a number as a string and outputs as many Xs as digits the imput number has.  
const char* getPlaceholder(char * number){

char *ptr; 

long wordAsNumb=strtol(number,&ptr,10);/* in order to later be able to count the number of digits the input 'number' has*/

char *currentPlaceholder='\0';//this variable is initialised and later we will later be added new Xs in case the input number has more than one digit. 


"222"--> 222
'\0'
.X \0'

while (wordAsNumb>1){

size_t len=strlen(currentPlaceholder); //this is the variable which will contain the placeholder (Xs) corresponding to the input number
char *output_string=malloc(len+2); /* adds two new characters to fit a new X (to increase the number of digits the input number has) and the "\0" */


strcpy(output_string,currentPlaceholder);
output_string[len]='X';
output_string[len+1]='\0';
/* in order to copy the currentPlaceholder value to 'output_string'. Then we add the two nex characters in the array*/
printf("String output is now %s\n ",output_string);

strcpy(currentPlaceholder,output_string);
free (output_string);
wordAsNumb/=10;

}

const char* finalPlaceholder=currentPlaceholder;
return finalPlaceholder;

}

However, I have stumbled upon the warning:

initialization makes pointer from integer without a cast [-Wint-conversion]

in line:

 char *output_string='X';

Any thoughts on what is wrong exactly?

Many thanks

Solution

nvidia-smi binary symlink created when you install the nvidia driver, as nvidia-340 in my case. Take a look:

darlene ➜   ls -la `which nvidia-smi` 

lrwxrwxrwx 1 root root 34 Mai 24 20:52 /usr/bin/nvidia-smi -> /etc/alternatives/x86_64-linux-gnu_nvidia_smi

darlene ➜   ls -la /etc/alternatives/x86_64-linux-gnu_nvidia_smi
lrwxrwxrwx 1 root root 34 Mai 24 20:52 /etc/alternatives/x86_64-linux-gnu_nvidia_smi -> /usr/lib/nvidia-340/bin/nvidia-smi

And the final binary comes from:

darlene ➜  dpkg -S /usr/lib/nvidia-340/bin/nvidia-smi
nvidia-340: /usr/lib/nvidia-340/bin/nvidia-smi

Comments

[Mark Kirby]

How did you install the driver ? PPA ? nvidia website ? or did you build it ?

[Shervin Gharib]

@markkirby, I installed it like what nvidia site said. 'sudo dpkg -i cuda-repo-ubuntu1404_7.5-18_amd64.deb' 'sudo apt-get update' 'sudo apt-get install cuda'

[Mark Kirby]

Did you not also install the driver ? You must install both CUDA and the driver as nvidia-smi is packaged with the driver.

[Shervin Gharib]

@markkirby no, I completely installed nvidia-352, Even I installed nvidia-340 but there is no nvidia-smi. My laptop has Intel 3000 and Nvidia 525M, is it important?

[Mark Kirby]

Yes you have a hybrid GPU right ? Intel and Nvidia ? First remove everything you installed with sudo apt-get purge nvidia* Then see here for the driver instructions askubuntu.com/questions/452556/…, then reinstall cuda, please see here for bumblebee docs, bumblebee-project.org/install.html

[h0r53]

In short, when defining an inline C-string you need to double quote the initial value. Here you have single quoted it, so the compiler attempts to treat it as an int instead of a null-terminated char array.

[Clifford]

The title "program with nesting warning in placeholder function" appears to have no connection to the actual question. What does that even mean?

[Oriol]

@Clifford. You are completely right. I wrote nesting instead of casting. That has been fixed already

[Clifford]

"placeholder function" suggests a temporary function that will later be replaced. That is not the sense you mean it here. Even with the typo fixed, it is misleading. I don't think the actual function name or what it is intended to do is particularly relevant in any case.

[Oriol]

You were all completely right in that the code was unclear and indeed with mistakes. I have added some comments that hopefully will make it clear. Hopefully now the idea of the code is clearer.

[fmoo]

It's super weird, but I can't find this alternative, even after reinstalling multiples times. Maybe the nvidia driver install is silently aborting or failing halfway through?

[Tomasz Gandor]

Wow, I've just learned something new - dpkg -S would not find symlinks (in case of alternatives). @fmoo - well, check all files with dpkg -L nvidia-390 (or whichever version you have), find nvidia-smi binary, and call it with absolute path, or add this location to your $PATH variable.