Very Computer

I need help with a sed statement.  

The problem:  Insert a single line of text before the first instance of a
string in a file.   The first character of the string is always the same,
the rest, variable.  There may be several lines of this string in the
variable-length file.  Example:

a
b
c
d
+something
+anything

- I want to insert the line "Insert" before the first line beginning with a
plus.  To my understanding of sed it would be:

cat file | sed -e '/^+/ i\Insert\'

But that's not working.  Note:  I've been able to write the fix in awk,
but it's annoying me that I can't do it in sed.

Can anyone provide insight?

--
.............................................................................

"War is an ugly thing, but not the ugliest of things;  The decayed and
 degraded state of m*and patriotic feelings which thinks that nothing
 is worth war is much worse.  A man who has nothing for which he is willing
 to fight, nothing which is more important than his own personal safety,
 is a miserable creature and has no chance of being free unless made and
 kept so by the exertions of better men than himself"
                                                          - John Stuart Mill

.............................................................................

   What does "not working" mean? What _exactly_ is the problem?

   That script works for me (though I don't use the unnecessary
   "cat").

--
    Chris F.A. Johnson                     <http://cfaj.freeshell.org>
    ==================================================================
    Shell Scripting Recipes: A Problem-Solution Approach, 2005, Apress
    <http://www.torfree.net/~chris/books/ssr.html>

cat /tmp/file| sed -e '/^+/{H
i\
Insert
:copy
n
b copy

Quote:}'

or:

cat /tmp/file| sed -e '/^+/{H' -e 'i\Insert' -e ':copy n' -e 'b copy }'

--
__Pascal Bourguignon__                     http://www.informatimago.com/

Nobody can fix the economy.  Nobody can be trusted with their finger
on the button.  Nobody's perfect.  VOTE FOR NOBODY.

Quote:>   What does "not working" mean? What _exactly_ is the problem?

GNU sed under Linux:

dswan:~$ cat /etc/passwd | sed  '/^vicki/ i\Insert'
sed: -e expression #1, char 12: Extra characters after command

--
.............................................................................

     "Be wary of enraging a little man, for he will retaliate with the
      force of a hundred little men"
                                                  -My Girlfriend, Lisa

.............................................................................

   Did you cut and paste the line or retype it?

   That works for me as is; but there's still no need for cat:

sed  '/^vicki/ i\Insert' /etc/passwd

--
    Chris F.A. Johnson                     <http://cfaj.freeshell.org>
    ==================================================================
    Shell Scripting Recipes: A Problem-Solution Approach, 2005, Apress
    <http://www.torfree.net/~chris/books/ssr.html>

Hmmm.. It still didn't work for me, even after typing it in manually:

dswan:~$ sed  '/^vicki/ i\Insert' /etc/passwd
sed: -e expression #1, char 12: Extra characters after command

What OS are you using?  Which sed?  Mine's: GNU sed version 3.02

--
.............................................................................

The welfare of the people in particular has always been the alibi of
tyrants, and it provides the further advantage of giving the servants of
tyranny a good conscience.

                                      - Albert Camus

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<snip>

<all letters and numbers above converted to "0">

The Netiquette limits on a sig are 4 lines total, including blank
lines, after a delimeter "-- " alone on a line.

I didn't read your article to see what quote you like this week.

I don't give a shit and I don't like having to read it.

Sigs are supposed to be sigs, not bulletin boards.

If you have something else that you want others to read/see, then
put it in URL in a legal sig.

Or, you will find your posts silently ignored and yourself often
silently killfiled.

I know the answer to your question too. If no one else had
helped you, you would be out of luck.

Many people who _could_ have answered your question, that
monitor this group, did not.

And Chris FAJ is just a *ing hypocrite: He'll freak if you
top post or fail to trim your posts but ignores large sigs
because _I_ don't let them pass and I have had the nerve to
stand up to the would-be bully in the past.

And the poor little chubby-wubby baby has never gotten over
it.

(and he doesn't know sed at all, obviously)

Fix your sig or I'll killfile you, JERK.

Get your *ing bulletin board out of my face or get out of my
newsreader.

Now, Bill Marcum, whom just tried to bully me too, will
post something *y.

Who cares. In real life I'd stomp his ass just like I
did here.

AC

--
alanconnor AT earthlink DOT net
Use your real return address or I'll never know you
even tried to mail me. http://www.veryComputer.com/

    Well, DON'T type it; cut and paste it.

Quote:> dswan:~$ sed  '/^vicki/ i\Insert' /etc/passwd
> sed: -e expression #1, char 12: Extra characters after command

> What OS are you using?  Which sed?  Mine's: GNU sed version 3.02

    Mine is GNU sed 4.1.1

    I tried 3.02 and got the same error as you. However this works (as
    I think someone else has already suggested):

sed  '/^vicki/i\
Insert' /etc/passwd

    Howver, on rereading your original post, I see that you only
    wanted the insert before the first occurrence. For that, someone
    else gave the sed solution. It was, I thought, a good
    adverti*t for awk.

--
    Chris F.A. Johnson                     <http://www.veryComputer.com/>
    ==================================================================
    Shell Scripting Recipes: A Problem-Solution Approach, 2005, Apress
    <http://www.veryComputer.com/~chris/books/ssr.html>

Quote:> Get your *ing bulletin board out of my face or get out of my
> newsreader.
> Now, Bill Marcum, whom just tried to bully me too, will
> post something *y.
> Who cares. In real life I'd stomp his ass just like I
> did here.

I am surprised that someone so focused on etiquette finds it acceptable to
make threats of *.

Switch to decaf, dude.

--
.............................................................................

"Woe to him who builds his house by unrighteousnesswho makes his neighbour
 serve him for nothing, and does not give him wages"
                                                           -Jeremiah 22:13

.............................................................................

Alan Connor is a troll.  Ignore him.

--
M?ns Rullg?rd

On Mon, 16 May 2005 06:43:09 GMT, Alan Connor

Quote:> The Netiquette limits on a sig are 4 lines total, including blank
> lines, after a delimeter "-- " alone on a line.

> I didn't read your article to see what quote you like this week.

> I don't give a shit and I don't like having to read it.

What do you know about 'Netiquette'?  Evidently not a lot, since you are
the one using 'inappropriate' language.

Quote:> Sigs are supposed to be sigs, not bulletin boards.

> If you have something else that you want others to read/see, then
> put it in URL in a legal sig.

> Or, you will find your posts silently ignored and yourself often
> silently killfiled.

Ooh, what a big boy, hiding behind an invalid address to flame someone
who has the temerity to have a couple of extra lines in a sig!  I know
which one is going in my killfile (and it isn't the flamed one)...

Quote:> Fix your sig or I'll killfile you, JERK.

> Get your *ing bulletin board out of my face or get out of my
> newsreader.

Such a big boy using '*' words.  Most of us grew out of that sort
of thing years ago.

PLONK.

Chris C

Your query prompted me to reinvestigate the 'i' command as although I have
been using sed for many years I had resigned myself to never being able
to get the 'i' command to work in one-liner scripts! After a few trials, I
now have the answer: break it up into a number of -e arguments, viz.,

sed -e '/^+/i\' -e 'Insert' file
or, sed -e '/^+/'i\\ -e 'Insert' file

As expected, identical one-liner syntax works for the 'a' command, also.

Note for MSDOS users: I found that the \ must not be inside any quotes,
i.e., you must use -e /^+/i\  OR  "/^+/"i\  OR  "/^+/i"\ but not "/^+/i\"

So, Daniel, you provided the incentive for me to master 'i' in one-liners
at last! In Unix, the usual work-around is to split the command over two
lines (but even this cop out is not available in the MSDOS OS).
--
John Savage                   (my news address is not valid for email)

I just reread your post since Chris pointed out you want only the
first instance changed, so my answer given earlier will need to become:

sed -e '1,/^+/{//i\' -e 'Insert' -e '}' file

--
John Savage                   (my news address is not valid for email)

Quote:> Your query prompted me to reinvestigate the 'i' command as although I have
> been using sed for many years I had resigned myself to never being able
> to get the 'i' command to work in one-liner scripts! After a few trials, I
> now have the answer: break it up into a number of -e arguments, viz.,

Much appreciated sir!

--
.............................................................................

"Forced counseling and "sensitivity training" are nothing more than
 buzzwords for political re-education"
                                         -Letter in NY Times, Feb 2, 2000

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Any reason for including that H instruction, Pascal?

Out of interest, any ideas on how you'd solve the problem were it changed
to the 5th (instead of the 1st) instance of a line matching /^+/ where the
inserted line was wanted?
--
John Savage                   (my news address is not valid for email)