Native data sets

Conventional text files and devices

A conventional text file has logical records delimited by the LF (line feed) character sequence. Most text editor programs create, and allow you to alter, conventional text files. Your PL/I programs can create conventional text files, or they can access text files that were created by other programs.

Devices for workstation products are the keyboard, screen, and printer. The names you use to refer to them in PL/I are:

/dev/null

A null output device (for discarding output)
An input device that indicates an EOF (end of file) when read

/dev/pts/n

A device that is associated with the interactive session

n

The number of the session that is assigned by the system

You can use the tty command to identify the device.
Example:

#tty
/dev/pts/3  

where /dev/pts/3 is the device that you can read from or write into using your PL/I program.

SYSIN

In an interactive session, the PL/I file name SYSIN maps to the standard input, which is the keyboard.

SYSPRINT

In an interactive session, the PL/I file name SYSPRINT maps to the standard output, which is the workstation screen.

In a non-interactive environment, SYSIN and SYSPRINT can be pipes or files.