在bash中检查当前分区的空闲磁盘空间

I am writing an installer in bash. The user will go to the target directory and runs the install script, so the first action should be to check that there is enough space. I know that df will report all file systems, but I was wondering if there was a way to get the free space just for the partition that the target directory is on.I am writing an installer in bash. The user wil