Shell Programming and Scripting

Pravin,

what does (first==1){print $9;first=0;next} and i<=NF(for(i=1;i<=NF;i++)) means ??

---------- Post updated at 03:36 PM ---------- Previous update was at 03:29 PM ----------

Pravin,,

what does if(first==1){print $9;first=0;next} for(i=1;i<=NF;i++) do...please if you can help me thru this...

I have tried my best to explain .

Code:

first

is a variable name. here i am using as flag.

Code:

NF

- No. of fields in a record.

Code:

{if(first==1){print $9;first=0;next}

#variable first is not having value initially so if condition will not satisfiled

Code:

for(i=1;i<=NF;i++){

#this is for loop which will go throgh record field by field.

Code:

if ($i~/\$AB_COMPONENTS/) {

#if any filed is match with pattern $AB_COMPONENTS then

Code:

split($i,a,"/");

#split that filed (in your case $AB_COMPONENTS/Sort/Sort.mpc) with delimiter as "/" and fill the array 'a'

Code:

print substr(a[3],1,(index(a[3],"."))-1)

here i am taking third element from array 'a'(i.e. Sort.mpc) and extracting string before . using index and substr.

Code:

first=1;

assigning 1 to variable first. because we found the pattern and perform operation as requested.

Now while reading your second line.

Code:

{if(first==1){print $9;first=0;next}

. Variable first is 1. if condition is satisfied and we can take field number 9 from second line and make first varibale zero.