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Batch editing files with ed

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Re: Batch editing files with ed

#11

Post by digi_owl »

John_KZ wrote: post #7

I've recently used EDLIN from an 80s version of MS-DOS. After spending 5 minutes with the manual, I realized it was the best line editor I've ever used. ed is very similar, but it doesn't come with a nice manual. The info page is chaotic and doesn't start from the beginning. You can cover typical usage in 5 lines, but no, you have to read through 25 pages of stuff just to figure out a sensible command. I just use vim…

My understanding is that man/info is meant more as a reference and less like a first time users guide.

Re: Batch editing files with ed

#12

Post by greenyoda »

zokier wrote: post #6

There is also ex, which is sort of cousin of ed, but also closer to nowdays more familiar vi(m).

It's closer because vi was built on top of ex -- vi's ":" commands are just ex commands. In fact, on my Linux box, /bin/ex is just a symbolic link to /bin/vi:

    $ ls -l /bin/ex
    lrwxrwxrwx 1 root root 2 Oct  2  2017 /bin/ex -> vi
The original code for vi was written by Bill Joy in 1976, as the visual mode for a line editor called ex that Joy had written with Chuck Haley. Bill Joy's ex 1.1 was released as part of the first BSD Unix release in March 1978.[1]

(Bill Joy went on to become a co-founder of Sun Microsystems.)

"ex" stood for the extended version of ed.

[1] https://en.wikipedia.org/wiki/Vi

Re: Batch editing files with ed

#14

Post by atsaloli »

Nice article, good to hear ed is not dead. =)

You could also just add the text after the matching line. A little simpler and more straight forward.

    $ cat > /tmp/ed-script
    /baz
    a
      - elephants
    .
    w
    q
    $ cat /tmp/2
    foo:
      - bar
      - baz
      - bananas
    $ cat /tmp/ed-script | ed /tmp/2
    33
      - baz
    47
    $ cat /tmp/2
    foo:
      - bar
      - baz
      - elephants
      - bananas
    $·

Re: Batch editing files with ed

#15

Post by textmode » 

   echo -e '/-baz\n+1\ni\n-elephant\n.\nw\nq\n'|ed foo
but ed requires a temp file in $TMPDIR to save changes

for speed, put $TMPDIR on memory file system

sed requires no temp file

   1.sed:
   /-baz/a\
   -elephant
   
   
   sed -f 1.sed foo|sed -a wfoo
works with all versions of sed, e.g., not all versions support "\n" in patterns nor so-called "edit-in-place" automatic temp file creation and removal

Re: Batch editing files with ed

#16

Post by samatman »

atsaloli wrote: post #14

Nice article, good to hear ed is not dead. =) You could also just add the text after the matching line. A little simpler and more straight forward. $ cat > /tmp/ed-script /baz a - elephants . w q $ cat /tmp/2 foo: - bar - baz - bananas $ cat /tmp/ed-script | ed /tmp/2 33 - baz 47 $ cat /tmp/2 foo: - bar - baz - elephants - bananas $·

My guess is that the - is replacing something like an org-mode cookie, which could be in a few states that one might want to preserve.

Re: Batch editing files with ed

#20

Post by yani »

textmode wrote: post #15

echo -e '/-baz\n+1\ni\n-elephant\n.\nw\nq\n'|ed foo but ed requires a temp file in $TMPDIR to save changes for speed, put $TMPDIR on memory file system sed requires no temp file 1.sed: /-baz/a\ -elephant sed -f 1.sed foo|sed -a wfoo works with all versions of sed, e.g., not all versions support "\n" in patterns nor so-called "edit-in-place" automatic temp file creation and removal

Sure, there is more than one way to do X. It will be useful to learn why you prefer sed over ed
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