I find an script with awk sitting around. I went through some online manuals, but I can't figure out exactly how it works. I can't post the whole program. Not allowed.

This is the line that is confusing me. I get when else is in the script

Code:

grep -v "^REM " $1| grep -v "JUNK;" | awk -F" " 'BEGIN{c=0;} { i=1; while ( i <= NF ) { f=$i; if ( f == "YUCK" ) printf("\n\nPROMPT %s \n",$0);

1. grep -v search line ,but ignore REM and JUNK
2. pipe to awk -F. -F does parsing of one line at a time

questions:
3. 'BEGIN {c=0}
Why do that? I don't see a 'c' variable anywhere else. When I googled this, you seem to do something like this when you add:

'BEGIN{for(c=0;c<50;c++)

4. { i=1; while ( i <= NF )
This a loop. that runs until the end of the line.

5. { f=$i;
didn't they just set i=1, and then increment it.
if f=$i, shouldn't that be a number instead, it appears it is what is actually in that field?

6. if ( f == "CREATE" )
condifitional logic

7. printf("\n\nPROMPT %s \n",$0);
short hand of the "then" part of conditional logic

\n\n I think means skip to lines right?
-- PROMPT? Does the word PROMPT get written? I did not see PROMPT as a key word?
-- %s? I know that printf has alot of variables you can use for formats. I did not find one for %s. what does that mean? Does anyone have a link for all the formats that work with printf?
-- /n $0)
-- another new line
-- print the enter line?

so if there is a CREATE, then print the whole line right?

After that I have a series of additional if then conditions, but I get most of it.


8. I see a -o, is that an "or" ? This is from a new line.

if ( ( f == "HERE" ) \
-o ( f == "THERE" ) \

-- if here or there? right?
-- why do we need "\", I know that means continue on a new line ,but why is that necessary here?


9. here is something else I don't get:

-o ( substr(f,length(f)-6,7) == "START" ) \

part of an if with an or
-- i know what substr does
-- f, is the variable that is being searched.
-- next it is check the length of f
-- so substr from length(f)-6 to 7.
-- then checking to see if it equals start




but the c variable is not used anywhere else?