求如何判断一个文件是否存在

redmarquis

#!/bin/sh
#watchdog.sh
files_watch=/wwwroot/herocenter/action/watchdog/dog_d.jpg
if [-r $files_watch];then
        rm -f $files_watch
        exit 1
else
        heroserver
fi

运行后总是提示
./watchdog.sh: [-r: command not found

lordbyorn

[ ]
should be [[ ]]
space before [[ and behind ]] is needed.

thus
if [[ -r $files_watch ]];then

KornLee

[ ]内的各项之间需要空格.

redmarquis

谢谢了，原来是这样，现在可以了，感谢两位的帮助