Shell Programming and Scripting

Hello:

I have a large file which contains lines like the following:

1/t123ab, &Xx:1:1234:12345:123456@ABCDEFG... at -$100.00%

/t is a tab, spaces are as indicated
the string "&Xx:1:1234:12345:123456$ABCDEFG..." has a slightly variable number of numbers and letters, but it always starts with "&Xx" and includes 4 ":"
I want to truncate that string to 20 characters plus "..." at the end.

So basically, I would like to do the following

sed 's/&Xx[any_number_of_characters]\.\.\./&Xx[17_characters]\.\.\./'

leaving all the rest untouched.
However

sed 's/&Xx.+\.\.\./test\.\.\./' did not make any changes

sed 's/&Xx........../test/' does change part of the string into "test", so the "." is recognized as representing "any character but new line"
sed 's/&Xx.{10}/test/' does not alter the file

I am using Linux Mint version 12

are there other ways to achieve this truncation? (awk?)

Thanks in advance.

Assumptions:
1) no more than 1 occurrence of the mentioned string (the one starting with &Xx) in a line,
2) no . character between the starting &Xx and ending ... in the string.

Code:

a='1	123ab, &Xx:1:1234:12345:123456@ABCDEFG... at -$100.00%'

echo "$a"|awk 'match($0,/&Xx[^.]*[.]{3}/){
if(RLENGTH>23)
 $0=substr($0,1,RSTART-1) substr($0,RSTART,20) substr($0,RSTART+RLENGTH-3)
}1'

1       123ab, &Xx:1:1234:12345:123... at -$100.00%

Code:

perl -lne '{ s/(&Xx:.*)\.{3}/substr($1,0,20)."..."/ge;print ;}'

This will avoid unnecessary substitutions:

Code:

perl -lne '/&Xx/ && do { s/(&Xx:.*?)\.{3}/substr($1,0,20)."..."/ge;print ;}'

The assumption is correct: there are no "." characters in the string except the three at the very end and there s only one occurrence of the string in a line.

There are however also lines that do not contain such a string.

Neither the awk command nor the perl -lne did truncate the string on my computer.

I have no clue why, as the output from elixir_sinari indicates that awk would do the job.

perl -lne '/&Xx/ && do { s/(&Xx:.*?)\.{3}/substr($1,0,20)."..."/ge;print ;}'

eliminated all lines that did not contain the string - which was not an intended outcome, but left the string untouched

@Tectone :
Yes please use my updated code with elixirs modification !

Anyways please take a look below..

Code:

$ perl -lne '{ s/(&Xx:.*?)\.{3}/substr($1,0,20)."..."/ge;print ;}' input_file
1       123ab, &Xx:1:1234:12345:123... at -$100.00%
somestring
newstring

Thats working fine for me !

Try this...

Code:

awk '{match($0,"([0-9]+.*&Xx)(.*)",a);print a[1],substr(a[2],0,17)"..."}' infile

If solaris, use nawk

--ahamed