sed print all lines after pattern match

Shell Programming and Scripting
1

HiCan someone show me how to print all lines from a file after a line matching a pattern using sed?Thanks

2

try

sed '1,/regex/d'

will not include the first pattern line.

example:

$ cat data
123
ABC
DEF
GHI
$ sed '1,/A/d' data
DEF
GHI
3

Thanks. Doesn't quite work perhaps because I am trying to pipe the lines through sed rather than read a file. What I am trying to do is lose the message of the day on stdout when running a command though ssh by preceding the command with an echo of a string "PARSE_FROM_HERE". The intention is to lose all of the MOTD stuff and just pick up the ls output. I have trouble posting code from here so I hope this is not too garbled, if so I will post it tonight: -

ssh [IP ADDRESS] "echo PARSE_FROM_HERE;ls -lrt" | sed '1,/PARSE_FROM_HERE/d'
4

What about:

ssh [IP ADDRESS] "ls -lrt"
5

Try:

sed '0,/PARSE_FROM_HERE/d'
6

:b:, that's right! I take a mistake.

7 
ssh [IP ADDRESS] "echo PARSE_FROM_HERE;ls -lrt " |sed '0,/PARSE_FROM_HERE/d'

This gives me the MOTD, the PARSE_FROM_HERE line and the ls output. If I substitute a 1 for the 0 I get the MOTD and nothing from the PARSE_FROM_HERE line. Which seems to be the opposite of what is expected from redraiment's results above.

8

Hi redraiment,

Actually you were right, but if the pattern is on the first line (if there is no MOTD) then it will not work. Besides it is not a general solution as 0,.. only works for GNU sed:

1,/pattern/ can be still be used if we use

printf '\nPARSE_FROM_HERE\n'

-or-

"echo;echo PARSE_FROM_HERE;...

instead.

9

Not sure if this is what you mean but this gives me MOTD and ls output with the PARSE_FROM_HERE string deleted: -

ssh [IP ADDRESS] "printf \"\nPARSE_FROM_HERE\n\";ls -lrt " |sed '1,/PARSE_FROM_HERE/d'
10

Thanks! sed range pattern will include more than one line. But, using the line number, can be the same line. like:

sed '1,1d'

:stuck_out_tongue:

11

Normally the MOTD does not get printed if you are executing a remote command with ssh, unless there is something wrong with your config, or perhaps you mean the banner? What happens if you do:

ssh [IP ADDRESS] "ls -lrt" 2>/dev/null
12

Yes sorry I guess it is a banner as it never changes. The redirection does seem to work giving me the ls output with no banner, seems I have been over complicating the issue. I wanted to simplify some code at work that uses a C program to intercept the banner by catching the echo of PARSE_FROM_HERE. I thought it could be done with sed instead but it seems that even that was not necessary as your redirection gives me the desired output. Thanks for the help.

---------- Post updated at 02:36 PM ---------- Previous update was at 01:51 PM ----------

This seems to be the answer to what I wanted in that it gives me just the pure ls -lrt output with no banner and no total string. Thanks for all the help folks...

ssh [IP ADDRESS] "echo PARSE_FROM_HERE;ls -lrt" 2>/dev/null |sed '/PARSE_FROM_HERE/,/$/d'
13

Hi, the total string comes from the ls command, so I would expect this to works too:

ssh [IP ADDRESS] ls -lrt 2>/dev/null | sed 1d

-or-

ssh [IP ADDRESS] "ls -ltr | sed 1d" 2>/dev/null
14

Yes they both work fine thanks, very compact. Much nicer and more readable than the original code. Having said that I don't understand the sed 1d, can you elaborate? Thanks

---------- Post updated at 03:22 PM ---------- Previous update was at 03:17 PM ----------

Ah got it, just deletes the first line. Thanks :slight_smile: