c program in linux to find out the number of processors

The following is a C program to find out the number of processors configured on a system.
We can make use of the function sysconf and pass the argument _SC_NPROCESSORS_CONF.
We need the header file unistd.h to use sysconf.

#include<stdio.h> #include<unistd.h> #include<stdlib.h> main() { long temp; temp=sysconf(_SC_NPROCESSORS_CONF); if(temp==-1) printf("Check the argument passed to sysconf"); printf("\nNo of configured processors : %d \n",temp); }

Save the program as get_processors.c. Compile and execute the code.

$ cc get_processors.c -o get_processors $ ./get_processors No of configured processors : 1