# psh command

The psh BASIC program executes a UNIX
command and captures the results in a D3 item. This command is an
alternative to the ! command, which allows capturing
the result of the UNIX command into a D3 item.

**For Windows:**Not Supported

## Syntax

```
psh unix.command{~}>{>} {file} item{(t}
```

## Parameter(s)

| unix.command | Any UNIX command. If it contains the > character, it is passed down to sh with its conventional usage. In this case, the > before the D3 item specification must be escaped by a ~ character. Only stdout is captured. To capture stderr, redirect it to stdout. |
| --- | --- |
| file | Optional D3 file name where the item is stored. If not specified, lst is used as a default. |
| item | Item name where the result is stored. If >> are used, with no space in between, the result of the UNIX command is appended to the end of the item, if it already exists. |
| t | Displays the result on screen, as well as storing it in the specified item. |

## Example(s)

Prints a calendar for the year
2003 and stores it in the item 2003 in the file tmp.

```
psh cal 2003 > tmp 2003
```
Transfers the file /usr/D3/myfile into the D3 item myfile
in the file lst (default). If the file does not exist on UNIX, the
error message displays on the terminal.

```
psh cat /usr/D3/myfile > myfile
```
Transfers the file /usr/D3/myfile into the D3 item myfile
in the file lst (default). stderr is redirected to stdout ('2>&1').
Therefore, if the file does not exist, the error message is in the
D3 item.

```
psh cat /usr/D3/myfile 2>&1 ~> myfile
```
Note: The *escape* of the >D3 redirection.

Stores the error messages produced by the two compilations of myprog1.c
and myprog2.c in the item myerrs. The second error messages are appended
to the end of the first.

```
psh cc myprog1.c 2>&1 ~> myerrs
psh cc myprog2.c 2>&1 ~>> myerrs
```
Note: The *escape* of the >D3 redirection and the `>>` to append data.

Changes the directory, lists
it, and stores the result in the item mylist.

```
psh cd /tmp; exec ls -l > mylist
```
Note:

- Use exec to avoid creating an intermediate shell.

- cd is not a UNIX command, but a sh keyword, and thus cannot use the exec command.

## See also

- [! command](https://d3codex.com/tcl/exclamation-command/)

---
Source: https://d3codex.com/tcl/psh-command/ - part of the D3Codex reference.