The following restrictions apply: 1) One thread will print "hello ", one thread will print "world", and the main function will print the trailing " ", 2) Ensure thread synchronization using pthread mutex /* Include Files */ #include /* External References */ extern void world( void ); extern void hello( void ); void main( int argc, char *argv[] ) { world(); hello(); printf( " " ); } /* world - print the "world" part. */ void world( void ) { printf( "world" ); } /* hello - print the "hello" part. */ void hello( void ) { printf( "hello " ); }