move-if-change

来自「LINUX下的源码工具,可自己分析,或者直接装在系统上作为应用」· 代码 · 共 14 行

#!/bin/sh
# Like mv $1 $2, but if the files are the same, just delete $1.
# Status is 0 if $2 is changed, 1 otherwise.
if test -r $2; then
  if cmp -s $1 $2; then
    echo $2 is unchanged
    rm -f $1
  else
    mv -f $1 $2
  fi
else
  mv -f $1 $2
fi