Questão de Linux Administration #019e3987

The yy command (or Y) in vi yanks (copies) the entire current line into the vi buffer. This is the standard command for copying a line in vi's normal mode.

How it Works

In vi, the y (yank) operator copies text into a buffer without deleting it. When followed by a motion, it yanks from the cursor to the target of the motion. The yy command is a special case that yanks the entire current line, equivalent to y_ or Y (if Y is not remapped). The buffer contents can then be pasted with p (after cursor) or P (before cursor).

Why the Correct Value is Right

• yy: This is the correct command. It yanks the current line into the buffer. The number prefix 1 is optional, so 1yy also works, but yy is the standard form.

Why the Incorrect Values are Wrong

• c: The c command is the change operator. It deletes text and enters insert mode. It does not copy.
• cc: The cc command changes (deletes and inserts) the current line. It does not copy.
• 1c: This is a change command with a count prefix. It changes one line (the current line) by deleting it and entering insert mode. It does not copy.
• 1y: While 1y would yank one line (the current line) if followed by a motion, 1y alone is incomplete. In vi, 1y without a motion is not a valid command; it would wait for a motion. The correct form is yy or 1yy.