## Подстановка $

```sh

[me@linuxbox ~]$ echo $USER

me

[me@linuxbox ~]$ echo $(ls)

Desktop Documents ls-output.txt Music Pictures Public Templates Videos

```

### Конвейер

```sh

file $(ls /usr/bin/* | grep zip)

/usr/bin/bunzip2:

symbolic link to `bzip2'

/usr/bin/bzip2:

ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV

), dynamically linked (uses shared libs), for GNU/Linux 2.6.9, stripped

/usr/bin/bzip2recover: ELF 32-bit LSB executable, Intel 80386, version 1

(SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.9, stripped

/usr/bin/funzip:

ELF 32-bit LSB executable, Intel 80386, version 1

(SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.9, stripped

```