UNIX环境高级编程7.7共享库7.9环境变量

// environ/hello1.c

#include <stdio.h>

int main()
{
    printf("hello, world
");
    return 0;
}

// g++ hello1.c -o hello1.a
// g++ -static hello1.c -o hello1.b , error occurs and I didn't find out why
// link error
// /usr/bin/ld: cannot find -lm
// collect2: ld returned 1 exit status