寻找正确的语法来查看bash变量并确定它是否为null,如果是,则执行…否则继续.
也许像if [$lastUpdated = null?;然后……别的……
只测试变量是否为空:
if [ -z "$lastUpdated" ]; then # not set fi
也许像if [$lastUpdated = null?;然后……别的……
if [ -z "$lastUpdated" ]; then # not set fi