linux shell /bin/sh: 5: pushd: not found

由于使用了/bin/sh 导致找不到pushd命令

切换回/bin/bash即可，但是我在shell中声明#!/bin/bash还是继续报错

看到一句解释如下：

   This has to do with /bin/sh being linked to /bin/dash instead of /bin/bash in ubuntu’s    latest releases. To fix it once and for all do the following:

使用下面的方法：

   # rm -f /bin/sh

   # ln -s /bin/bash /bin/sh