什么是自动换行并对齐文本文件以使输出看起来像手册页的命令：
All of these system calls are used to wait for state
changes in a child of the calling process, and obtain
information about the child whose state has changed. A
state change is considered to be: the child terminated; the
child was stopped by a signal; or the child was resumed by
a signal. In the case of a terminated child, performing a
wait allows the system to release the resources associated
with the child; if a wait is …