# bash

* log everything to a file:

```
#!/bin/bash
(
...
) 2>&1 | tee -a file
```

* more subshells may potentially be needed:

```
#!/bin/bash
((
...
) 2>&1) | tee -a file
```

* create a file from a heredoc:

```
cat << EOF > /tmp/yourfilehere

These contents will be written to the file.
        This line is indented.
EOF
```

* find files holding a mountpoint open:

```
$ dmsetup info -c | grep root

data-root        254   8 L--w    1    1      0 LVM-C6c8ojMf4YLaSZearY2kTlKbL23Hue9RFUByBbzCncyPWemQGMz9EnmHyNjfJdxy
$ lsof | grep "254,8"
```