在配置qmail时,前面的步骤都做了,开始执行编译 Qmail 及相关软件make setup check,但编译到一半的时候就出现问题,uto-str.c: In function `main': auto-str.c:17: warning: return type of `main' is not `int' ./load auto-str substdio.a error.a str.a substdio.a(substdo.o)(.text+0x43): In function `allwrite': : undefined reference to `errno' collect2: ld returned 1 exit status make: *** [auto-str] Error 1 这个问题该如何解决请高人指点