Questions

This is a common error while compiling C program in Linux. This error occurs when you are using pthread_create function to create threads in your programs.

To fix this problem ensure following points:
Include header file pthread.h in your program.
Add –lpthread linker flag with compilation command.
1- Include Header file
#include <stdio.h>
#include <pthread.h>
...
...
2- Compile command
gcc main.c -o main -lpthread

All automobiles uses satellite communication channel for their GPS devices.

A star is a self luminous astronomical object and shines due to internal radiation from the enrgy sources. All stars are held together by their own gravity called Gravitational force.