bsdtar 的 -q 选项

Question

我在 bash 脚本中遇到了以下代码。

# See if bsdtar can recognize the file
if bsdtar -tf "$file" -q '*' &>/dev/null; then
   cmd="bsdtar"
else
continue

'-q' 选项是什么意思？我在 bsdtar 命令的帮助信息中没有找到任何信息。

谢谢！

Answer 1

来自 bsdtar man page:

-q (--fast-read)
     (x and t mode only) Extract or list only the first archive entry
     that matches each pattern or filename operand.  Exit as soon as
     each specified pattern or filename has been matched.  By default,
     the archive is always read to the very end, since there can be
     multiple entries with the same name and, by convention, later
     entries overwrite earlier entries.  This option is provided as a
     performance optimization.