Sed mode space & hold Space

Pattern Space: The buffer that holds the current input line;

Hold space: As a secondary buffer, you can interact with the pattern space, but the command cannot directly act on the hold space.

As defined above, the pattern space and the hold space are two separate buffers that can be interacted with, and the command can address the pattern space but cannot address the hold space.

One, mode space:

Rows that are matched by a pattern are read into the pattern space. Used for further operations; in multiline mode,' \ n ' can be used to match any newline character in the pattern space (the result of the n command), except for the line breaks at the bottom of the single-mode space . ^ matches the first of multiple lines, $ matches the tail of multiple lines, not the beginning of each line and the end of the line.

Second, to maintain space:

You can interact with the pattern space through h,h,g,g.

Sed mode space & hold Space