tee Command

Purpose

Displays the output of a program and copies it into a file.

Syntax

tee [ -a ] [ -i ] [ File ... ]

Description

The tee command reads standard input, then writes the output of a program to standard output and simultaneously copies it into the specified file or files.

Flags

Item	Description
-a	Adds the output to the end of File instead of writing over it.
-i	Ignores interrupts.

Exit Status

This command returns the following exit values:

Item	Description
0	The standard input was successfully copied to all output files.
>0	An error occurred.

Note: If a write to any successfully opened File operand is not successful, writes to other successfully opened File operands and standard output will continue, but the exit value will be >0.

Examples

To view and save the output from a command at the same time:
```
lint program.c | tee program.lint
```
This displays the standard output of the command lint program.c at the workstation, and at the same time saves a copy of it in the file program.lint. If a file named program.lint already exists, it is deleted and replaced.
To view and save the output from a command to an existing file:
lint program.c | tee -a program.lint
This displays the standard output of the lint program.c command at the workstation and at the same time appends a copy of it to the end of the program.lint file. If the program.lint file does not exist, it is created.

Files

Item	Description
/usr/bin/tee	Contains the tee command.