Running a macro till the end of text file in Emacs

Question

I have a text file with some sample content as shown here:

Sno = 1p Sno = 2p Sno = 3p 

What i want is to remove the p from each of the columns. With this intention i write a macro:

M-x //go to buffer C-x (//start the macro C-s = // search for equalto sign RET C-f C-f // reach to te alphabet 'p' DEL // Delete C-n  C-x )//go to new line and Close the macro definition  C-x e 

Pressing e twice will remove p, but in case i want to do the same stuff till the end of file, how can i do it i can't keep pressing e if i have 20000 such lines. What should be done??

Please donot suggest regex, as this is a sample example, not the actual case. Please donot suggest any elisp, i am comfortable with remembering shortcutf for emacs.

Answer 1

M-0 C-x e to repeat last macro until an error happens (after the final line, either C-s = or C-n will be an error).

You may hear an annoying beep.

Answer 2

You can use the "apply-macro-to-region-lines" function to apply the last defined keyboard macro to all lines in a region. So, the steps you follow are:

1. Define your keyboard macro (which you had already done but I've added another C-f to the 3rd line):

   C-x ( C-s = RET C-f C-f C-f DEL C-n C-x )

2. Select the whole buffer with the "mark-whole-buffer" command (by default, it's bound to C-x h). Alternatively, if you just want to change a certain number of lines, just select the lines you want changed.

3. Run the "apply-macro-to-region-lines" function (by default, it's bound to C-x C-k r).

All the p's will be removed.