Title: Fun tip #2: Display trailing spaces using ed
       Author: Solène
       Date: 29 November 2018
       Tags: unix fun-tip openbsd
       Description: 
       
       .Dd November 29, 2018
       .Dt "Show trailing spaces using ed"
       This second fun-tip article will explain how to display trailing
       spaces in a text file, using the
       .Lk https://man.openbsd.org/ed ed(1)
       editor.
       ed has a special command for showing a dollar character at the end of
       each line, which mean that if the line has some spaces, the dollar
       character will spaced from the last visible line character.
       
       .Bd -literal -offset indent
       $ echo ",pl" | ed some-file.txt
       453
       .Dd November 29, 2018$
       .Dt "Show trailing spaces using ed"$
       This second fun-tip article will explain how to display trailing$
       spaces in a text file, using the$
       .Lk https://man.openbsd.org/ed ed(1)$
       editor.$
       ed has a special command for showing a dollar character at the end of$
       each line, which mean that if the line has some spaces, the dollar$
       character will spaced from the last visible line character.$
       $
       \&.Bd \-literal \-offset indent$
       \$ echo ",pl" | ed some-file.txt$
       .Ed
       
       This is the output of the article file while I am writing it. As you
       can notice, there is no trailing space here.
       
       The first number shown in the ed output is the file size, because ed
       starts at the end of the file and then, wait for commands.
       
       If I use that very same command on a small text files with trailing
       spaces, the following result is expected:
       
       .Bd -literal -offset indent
       49
       this is full    $
       of trailing  $
       spaces      !    $
       .Ed
       
       It is also possible to display line numbers using the "n" command
       instead of the "p" command.
       This would produce this result for my current article file:
       .Bd -literal -offset indent
       1559
       1       .Dd November 29, 2018$
       2       .Dt "Show trailing spaces using ed"$
       3       This second fun-tip article will explain how to display
       trailing$
       4       spaces in a text file, using the$
       5       .Lk https://man.openbsd.org/ed ed(1)$
       6       editor.$
       7       ed has a special command for showing a dollar character at the
       end\
        of$
       8       each line, which mean that if the line has some spaces, the
       dollar$
       9       character will spaced from the last visible line character.$
       10      $
       11      .Bd -literal -offset indent$
       12      \$ echo ",pl" | ed some-file.txt$
       13      453$
       14      .Dd November 29, 2018\$$
       15      .Dt "Show trailing spaces using ed"\$$
       16      This second fun-tip article will explain how to display
       trailing\
       \$$
       17      spaces in a text file, using the\$$
       18      .Lk https://man.openbsd.org/ed ed(1)\$$
       19      editor.\$$
       20      ed has a special command for showing a '\\\$' character at the
       e\
       nd of\$$
       21      each line, which mean that if the line has some spaces, the
       '\\\$\
       '\$$
       22      character will spaced from the last visible line character.\$$
       23      \$$
       24      \\&.Bd \\-literal \\-offset indent\$$
       25      \\\$ echo ",pl" | ed some-file.txt\$$
       26      .Ed$
       27      $
       28      This is the output of the article file while I am writing it.
       As\
        you$
       29      can notice, there is no trailing space here.$
       30      $
       31      The first number shown in the ed output is the file size,
       becaus\
       e ed$
       32      starts at the end of the file and then, wait for commands.$
       33      $
       34      If I use that very same command on a small text files with
       trail\
       ing$
       35      spaces, the following result is expected:$
       36      $
       37      .Bd -literal -offset indent$
       38      49$
       39      this is full    \$$
       40      of trailing  \$$
       41      spaces      !    \$$
       42      .Ed$
       43      $
       44      It is also possible to display line numbers using the "n"
       comman\
       d$
       45      instead of the "p" command.$
       46      This would produce this result for my current article file:$
       47      .Bd -literal -offset indent$
       .Ed
       This shows my article file with each line numbered plus the position
       of the last character of each line, this is awesome!
       
       I have to admit though that including my own article as example is
       blowing up my mind, especially as I am writing it using ed.