How to create shared library in Linux invironment.

#ifndef PASSWORD_HHH #define PASSWORD_HHH #include <stdio.h> #include <stdlib.h> static char pas[50]; char* password (void); #endif password.cpp
// I specially didn't use C++ libraries for // the compatibility with C compiler #include "password.hh" char* password (void) { char file[50]; FILE *in; sprintf(file,"%s/.password", getenv("HOME")); if ( (in = fopen(file,"r")) == NULL ) { printf("You must create file .password"); printf(" in you home directory\n"); exit(EXIT_FAILURE); } fscanf(in,"%s",pas); fclose(in); return pas; }