Global/Limited Search/Replace

To perform text search or replace we must use ex commands by typing:
:<command><ret>
The command appears at the bottom of the screen.
To execute more ex commands in sequence, it is usefull to switch from vi to ex mode, to obtain the ex : prompt.

Q	switch from vi to ex mode
vi	switch from ex to vi mode

When ex mode is entered from vi Q command, it is possible to execute ex commands on one or more lines. In general single ex commands can be entered with the : colon prefix. Commands that require entering \ can be entered only when in ex mode (Q command) and are platform dependent.

Advanced Pattern Matching Syntax
Q Commands
:%s/[space tab][space tab]*/\	split whole file in one word lines
:%s/$/\	double spacing text
:g/pattern/p	search and print pattern in whole file
:g!/pattern/p	print all lines NOT including
	pattern in whole file
:init,end g/pattern/p	search and print from init
	to end line in file
:/pattern1/,/pattern2/p	search and print from pattern1
	to pattern2




In ex commands g means global, p means print. In the Advanced matching table are shown the following features.

:[space tab][space tab]*	regular expression that means:
	any <space> or <tab> followed by zero or more
	<space>s and/or <tab>s
%	operate on whole file; synonim of 1,$
/$/	end of line




All matching lines are printed on screen and the following message appears on the bottom line:
[Hit return to continue]
Cursor moves to last matching pattern found.

A complete overview of pattern searching with or without text substitution is given in the Special and Common pattern handling tables.

Special Pattern Searching Syntax
:g/pattern/s/old/new/g	search pattern in whole file and change old to new
	globally on that line
:%s/[space tab]*$//	remove blanks and/or tabs at EOL in whole file
/^pattern	search pattern at BOL (beginning of line)
/pattern$	search pattern at EOL (end-of-line)




Common Pattern Substitution Syntax
:s/old/new	change only first occurrence of old to new on
	current line
:s/old/~	repeat previous change on another line
:&	repeat previous substitute command
:s/old/\unew	change only first occurrence of old to New on
	current line
:s/old/\lNEW	change only first occurrence of old to nEW on
	current line
:s/old/\Unew	change only first occurrence of old to NEW on
	current line
:s/old/\LNEW	change only first occurrence of old to new on
	current line
:s/old/new/g	change every occurrence of old to new on current line
:50,100 s/old/new/g	change every occurrence of old to new from line
	50 to line 100
:% s/old/new/g	change every occurrence of old to new in whole file
:% s/old/new/gc	as previous command but with confirm. It displays
	entire line where string has been located, string will
	be marked by a series of ^^^^. answer y to make
	replacement, <ret> for no replacement
:s	repeats last substitution




Recognized colon command for init end/or end :

:$	last line in file
:.	current line
:%	abbreviation for 1,$ (whole file)
:g	whole file
:n	nth line in file
:.-n	nth line before current line
:.+n	nth line after current line
:n,m	from line n to line m
:.-n,.+m	nth preceding line to mth following line




To visualize non-printing control characters hidden in a file:

:l	$ indicates EOL, ^I indicates tab.




To visualize tabs and EOL for whole file:

:set list
:set nolist	toggle back to normal mode