当我与 cvs update 结合使用时，-PAd 是什么意思？
答案1
要了解任何命令的作用，请使用 Unix/Linux/OS X 手册页：
男人简历
无论如何，直接从“更新选项”标题下的那些页面：
-P
Prune empty directories. See see node `Removing directories' in the CVS
manual.
-A
Reset any sticky tags, dates, or -k options. See see node `Sticky tags'
in the CVS manual, for more information on sticky tags/dates.
-d
Create any directories that exist in the repository if they're missing
from the working directory. Normally, update acts only on directories
and files that were already enrolled in your working directory.
This is useful for updating directories that were created in the reposi-
tory since the initial checkout; but it has an unfortunate side effect.
If you deliberately avoided certain directories in the repository when
you created your working directory (either through use of a module name
or by listing explicitly the files and directories you wanted on the
command line), then updating with -d will create those directories,
which may not be what you want
答案2
基本上，它将签出的分支恢复到最新修订版。
-P 修剪空目录 -A 重置粘性标签 -d 创建存储库中存在但本地缺少的目录。