— Macro: .DT

Set tabs every 0.5 inches. Since this macro is always executed during a call to the TH macro, it makes sense to call it only if the tab positions have been changed.

— Macro: .PD [nnn]

Adjust the empty space before a new paragraph (or section). The optional argument gives the amount of space (default unit is ‘v’); without parameter, the value is reset to its default value (1 line in nroff mode, 0.4v otherwise).

This affects the macros SH, SS, TP, LP (as well as PP and P), IP, and HP.

— Macro: .AT [system [release]]

Alter the footer for use with AT&T manpages. This command exists only for compatibility; don't use it. The first argument system can be:

3

7th Edition (the default)

4

System III

5

System V

An optional second argument release to AT specifies the release number (such as “System V Release 3”).

— Macro: .UC [version]

Alters the footer for use with BSD manpages. This command exists only for compatibility; don't use it. The argument can be:

3

3rd Berkeley Distribution (the default)

4

4th Berkeley Distribution

5

4.2 Berkeley Distribution

6

4.3 Berkeley Distribution

7

4.4 Berkeley Distribution