In awk, how do I prepend a string to a pattern search print

If the object is to learn awk then you could try out some of the other functionality. This relies a bit on the formatting of your file but then, so do the other answers, so

awk -F'>|<| ' -v OFS=" = " '/To:|From:|Cc:/{print "E-mail", $(NF-1)}' file

E-mail = [email protected]
E-mail = [email protected]
E-mail = [email protected]

First you can set up your input field separator -F as an extended regular expression, an ERE, so that it breaks your input line $0 on < or > or

-F'>|<| ' 

Doing this cleans the extra character from the end of the email address but leaves $1 empty (because of the leading <), $2 contains your filtering field, $3 the email address and there is an empty $4 at the end (because of the trailing >)

Then being lazy you can set the output field separator to = so whenever you print a series of fields the default behaviour is to insert = and not just between the fields

-v OFS=" = " 

Your filtering is the same on $0 but when you print, because you split the input string $0 into 4 (and the number of fields, the special awk variable, NF=4) you want to print $3, which is also $(NF-1) in this case

'/To:|From:|Cc:/{print "E-mail", $(NF-1)}' file

And because you have pulled your filter field out expressly then you can guard against an accidental match elsewhere in $0 by looking for an explicit match in $2 if you want.

'$2=="To:"||$2=="From:"||$2=="Cc:"{......

Command

awk -F ":" '/To|Cc|From/{gsub(">","",$2);print "email ="$2}' filename

output

email = [email protected]
email = [email protected]
email = [email protected]

Python

#!/usr/bin/python
import re
k=re.compile(r'To|Cc|From')
q=open('filename','r')
for i in q:
    if re.search(k,i):
        w=i.split(":")[1].replace(">","")
        print "email = {0}".format(w).strip()

output

email =  [email protected]
email =  [email protected]
email =  [email protected]

It looks like the following would do what you need:

awk '/To:|From:|Cc:/ {$2=substr($2,1,length($2)-1); print "email = ", $2 }' file

This bit:

{$2=substr($2,1,length($2)-1)

Takes the second element in the string, which is something like [email protected]>, and removes the last character, >.

Then you just print the string you want "email = ", along with the edited second element, $2:

print "email = ", $2

The result looks like this:

email =  [email protected]
email =  [email protected]
email =  [email protected]

It's worth familiarizing yourself with how print works: https://www.gnu.org/software/gawk/manual/html_node/Print-Examples.html