tabs1

General Options

-Tname

Tell tabs which terminal type to use. If this option is not given, tabs will use the $TERM environment variable. If that is not set, it will use the ansi+tabs entry.

-d

The debugging option shows a ruler line, followed by two data lines. The first data line shows the expected tab-stops marked with asterisks. The second data line shows the actual tab-stops, marked with asterisks.

-n

This option tells tabs to check the options and run any debugging option, but not to modify the terminal settings.

-V

reports the version of ncurses which was used in this program, and exits.

The tabs program processes a single list of tab stops. The last option to be processed which defines a list is the one that determines the list to be processed.

Implicit Lists

Use a single number as an option, e.g., “-5” to set tabs at the given interval (in this case 1, 6, 11, 16, 21, etc.). Tabs are repeated up to the right margin of the screen.

Use “-0” to clear all tabs.

Use “-8” to set tabs to the standard interval.

Explicit Lists

An explicit list can be defined after the options (this does not use a “-”). The values in the list must be in increasing numeric order, and greater than zero. They are separated by a comma or a blank, for example,

tabs 1,6,11,16,21
tabs 1 6 11 16 21

Use a “+” to treat a number as an increment relative to the previous value, e.g.,

tabs 1,+5,+5,+5,+5

which is equivalent to the 1,6,11,16,21 example.

Standard Tab Stops

POSIX defines several lists of tab stops.

-a

Assembler, IBM S/370, first format
1,10,16,36,72

-a2

Assembler, IBM S/370, second format
1,10,16,40,72

-c

COBOL, normal format
1,8,12,16,20,55

-c2

COBOL compact format
1,6,10,14,49

-c3

COBOL compact format extended
1,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,67

-f

FORTRAN
1,7,11,15,19,23

-p

PL/I
1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61

-s

SNOBOL
1,10,55

-u

UNIVAC 1100 Assembler
1,12,20,44

Margins

A few terminals expose a means of changing their left and right margins. tabs supports this feature with an option.

+m margin

The effect depends on whether the terminal has the margin capabilities:

•

If the terminal provides the capability for setting the left margin, tabs uses this, and adjusts the available tab stop widths.

•

If the terminal does not provide the margin capabilities, tabs imitates their effect, putting tab stops at appropriate places on each line. The terminal's left margin is not modified.

If the margin parameter is omitted, the default is 10. Use +m0 to reset the left margin, that is, to make it the left edge of the terminal's display. Before setting a left margin, tabs resets the margin to reduce problems that might arise from moving the cursor to the left of the current left margin.

When setting or resetting the left margin, tabs may also reset the right margin.