How do I join two lines in vi?

Question

I have two lines in a text file like below:

S_F
_ID_T_O.DAT


        

Answer 1

This should do it:

J

Answer 2

If you want to join the selected lines (you are in visual mode), then just press gJ to join your lines with no spaces whatsoever.

This is described in greater detail on the vi/Vim Stack Exchange site.

Answer 3

Vi or Vim?

Anyway, the following command works for Vim in 'nocompatible' mode. That is, I suppose, almost pure vi.

:join!

If you want to do it from normal command use

gJ

With 'gJ' you join lines as is -- without adding or removing whitespaces:

S<Switch_ID>_F<File type>
_ID<ID number>_T<date+time>_O<Original File name>.DAT

Result:

S<Switch_ID>_F<File type>_ID<ID number>_T<date+time>_O<Original File name>.DAT

With 'J' command you will have:

S<Switch_ID>_F<File type> _ID<ID number>_T<date+time>_O<Original File name>.DAT

Note space between type> and _ID.