-x和-c字符串比较选项有什么作用？

Question

当我遇到以下情况时，我正在移植另一个shell脚本：

if [[ ! -x $DVDREC ]]; then
  print "ERROR: $DVDREC not found. Exiting ..."
  exit 1
fi

if [[ ! -c ${DVDDEV} ]]; then
  print "ERROR: ${DVDDEV} not found. Exiting ..."
  exit 1
fi

我想知道-c和-x选项实际上对存储的字符串做了什么 在DVDREC和DVDDEV？

Answer 1

来自bash shell中的“帮助测试”：

  -c FILE        True if file is character special.
  -x FILE        True if the file is executable by you.

Answer 2

// man test

   -c FILE
          FILE exists and is character special

   -x FILE
          FILE exists and execute (or search) permission is granted

Answer 3

引用man test：

   -c FILE
          FILE exists and is character special

   -x FILE
          FILE exists and execute (or search) permission is granted