wrong sed operation

shridhar22 · 08-28-2012, 12:08 AM

Code:

rec=`$CCRCQUERY -id -engineer -createdt -checkindt $CCRNum`

tHE CODE GIVES THE FOLLOWING VALUE TO THE REC VARIALBLE:

ID |ENGINEER|CREATEDT |CHECKINDT
-------------|--------|----------|----------
CCMPR00684153|vijays |06-29-2009|07-06-2009

NOW I WISH to extract engineer cretedt and chedindt from rec.

Im using the following code to do so

Code:

engr=`echo $rec | awk -F\| '{print $2}' | sed 's/ //g'`
createdt=`echo $rec | awk -F\| '{print $3}' | sed "s/ //g"`
checkindt=`echo $rec | awk -F\| '{print $4}' | sed 's/ //g'`

but the value of engr is coming ENGINEER but i want vijays
value of createdt is coming CREATEDT but i want 06-29-2009 and simillarly for checkindt.

PLEASE HELP ME PLEASEEEEEEEEE

pan64 · 08-28-2012, 12:35 AM

the problem is that you got 3 lines, awk parses the first line, not the third. You would need another awk:

Code:

awk -F\| ' NR == 3 { gsub (" ", ""); print $2 } '

you do not need sed, gsub will remove spaces

(not tested)

shridhar22 · 08-28-2012, 12:36 AM

IF I USE

Code:

 rec=`$CCRCQUERY -id -engineer -createdt -checkindt $CCRNum | grep CCMPR`

The rec varialble doesnt have any value.... why does it not grep the lower line?

David the H. · 08-28-2012, 11:47 AM

Actually, we don't really need to use any external tools at all to do this.

Code:

rec='ID |ENGINEER|CREATEDT |CHECKINDT
-------------|--------|----------|----------
CCMPR00684153|vijays |06-29-2009|07-06-2009'

shopt -s extquote			#needed for the next line
rec="${rec##*$'\n'}"			#removes everything up to the final newline

IFS='|' read -r id engr createdt checkindt <<<"$rec"	#read with the IFS setting splits the remaining line directly into the desired variables (plus the unneeded id field).

This version uses parameter substitution and the bash/ksh specific ansi-c style quoting (along with the extquote shell option, necessary when you want to expand them inside parameter substitutions).

It also uses a here string to pass the variable to read.

If you need posix-style portability, we can use a simple loop instead.

Code:

while IFS='|' read a b c d; do
	id=$a
	engr=$b
	createdt=$c
	checkindt=$d
done <<HEREDOC
$rec
HEREDOC

The here document provides the input to the loop, after expanding the variable. Since all we're interested in is the last line, we only need to iterate over all lines, and only the final values will remain in variables when the loop terminates.

David the H. · 08-30-2012, 07:15 PM

BTW, here's an even quicker way to target only the last line, if you are using a recent version of bash (v4+).

Code:

mapfile -t rec <<<"$rec"	#convert the variable to a line-separated array.
IFS='|' read -r id engr createdt checkindt <<<"${rec[@]: -1}"	#process the final entry.

From version 4.2 you can replace the last part with a negative array index: e.g. "${rec[-1]}"