MPE/iX Shell and Utilities Reference Manual, Vol 2

vi(1) MPE/iX Shell and Utilities vi(1)

Current Position Pointer

The current position pointer indicates a position in the text that is currently being edited (or

has just been edited). In Ex mode, the current position pointer is just the line number of the

line being edited. In Vi mode, the pointer gives this line number plus the position of the cur-

sor within the line. The line indicated by the current position pointer is always on the screen.

Display Conventions

vi uses three display conventions that should be noted.

• vi displays the input for search commands (/ and ?), Ex commands (:), and system com-

mands (!) on the bottom line of the screen. Error and informational messages also appear

on this line.

• If the last line in the ﬁle is above the bottom of the screen, screen lines beyond the end of

the ﬁle are displayed with a single ˜ character in column one.

• In certain infrequent circumstances (usually involving lines longer than the width of the

screen), vi is unable to ﬁll the display with complete lines. In this case, one or more

screen lines are shown with a single @ character in column one.

These lines are not part of the ﬁle content and should be ignored.

Vi Command Summary

Vi commands may be divided into several categories.

(a) Scrolling commands adjust the position of text on the screen. The current position

pointer only changes if the current line is scrolled off the screen. For example,

CTRL-E scrolls the text on the screen up one line. The cursor remains pointing to the

same text that it was pointing to, unless that text is moved off the screen.

(b) Movement commands move the cursor in the ﬁle. For example, the character j moves

the cursor down one line and the screen is scrolled only if necessary. There are two

types of movement commands: absolute movements and context-dependent move-

ments. An absolute movement moves the cursor, regardless of the nature of the sur-

rounding text; for example, j always moves the cursor down one line. A context-de-

pendent movement moves the cursor based on the nature of the text; for example, w

moves the cursor to the beginning of the next word, so it must look at the text to de-

termine where the next word begins.

(d) Text insertion commands let you add new text to the existing text.

1-648 Commands and Utilities