Shell Programming and Scripting

I will have a look at the first piece of code you gave me and see what the affect is.
I think i got the -e option of sed now, thanks also.
The 's/findstr/repstring/g' is about the most common syntax of sed i can actually understand.
which is why i hate why i cant understand a simple thing like append.
I understand it appends a line after the line in which a pattern is found.
I also understand the i option which inserts a string before the line in which a pattern is found.
Is what i say right?
Anyhow, what i am trying to say what i want which is "appending" text to a same line in which a pattern is found is obviously not being correctly asked so i apologize,
Let me test the affects of the first code example you gave me and see if i get it, thanks.

Moderator's Comments:

Please use CODE and ICODE tags when displaying sample input, sample output, and code segments (as required by forum rules). Using tags is helpful when displaying text to help determine whether you are talking about generic, descriptive text versus explicit exact text to be added, matched, removed, ... When the different between a single <space> versus one or more <space> and/or <tab> characters matters, CODE or ICODE tags are crucial. Use CODE tags when displaying one or more complete lines of sample input, sample output, or code. Use ICODE tags when displaying partial lines of sample input, sample output, or code.

Almost. Yes, the sed a command appends one or more lines of text starting on the line after the addressed line. No, the sed i command (not option) does not insert a string at the start of a line; it inserts one or more lines of text before an addressed line.
Nothing that you have described involves appending LINES of text nor inserting LINES of text. Nothing that you have described can be done with a sed a or i command because you DO NOT want to create new lines of text, you only want to add strings of text to existing lines of text, delete strings of text from existing lines of text, or modify strings of text on existing lines of text. All three of these are done with the sed s command, i.e., commands of the form that you said you already understand:

Code:

's/findstr/repstring/g'

which would more correctly be written as:

Code:

s/BRE/replacement/flags

where BRE is a basic regular expression (which in its simplest form could just be a string of regular characters, but could also be an extremely complex expression matching repeated complex patterns); replacement could be a simple string of zero or more regular characters or could include meta-characters that refer to selected portions of the text matched by the BRE; and flags (including, but not limited to, the frequently over-used g flag). And, even in that simple form, the / characters separating the command name (s), the BRE, the replacement, and the flags can be replaced by almost any other character (except the <newline> character) which can be useful when the BRE or the replacement contain <slash> characters.

Note also that the sed s command, the ed s command, the ex s command, the vi :s command, and the awk sub() and gsub() functions all behave very similarly (although the awk sub() and gsub() functions use extended REs (EREs) instead of the BREs used by sed, ed, ex, and vi.

I understand that there are many new things for you to come to grips with. Did you try any of the proposals and comprehend the results? Why don't you post those and your pertaining questions?
Do you understand the concept of "addresses" in sed? The concept of regexes and details hereof (like [Dd], meaning one single char, either "D" or "d")?