user input howto using awk

cmontr · 09-25-2007, 05:11 PM

Hello guys, if anyone can tell me how can I modify the script below that would asks users input to print the value...Thanks much...

code:

#!/bin/sh
# ctest.awk

BEGIN{ headingFound = 0; }
/^cquestion:/ { headingFound = 1; }
/^dn:/ {
if( headingFound == 1 ){
print $2;
headingFound = 0;
}
}

# awk -f ctest.awk a.txt > b.txt

currently this script is supposed to ask what the cquestions is like "what is your name?" then next it should print all the dn values from the a.txt file which is a big file and sections of it like:

dn: uid=poi.1111,ou=abc,o=cc.com
authpassword;orclcommonpwd: {SHA}adhnbckhsypzx=
businesscategory: abc
createtimestamp: 20050709198316x
creatorsname: cn=bulkload
modifiersname: cn=bulkload
modifytimestamp: 20050709198316x
objectclass: top
objectclass: cuser
cquestion: xyf88561
dn: uid=poi.2222,ou=def,o=dd.com
authpassword;orclcommonpwd: {SHA}adhnbckhsypzx=
businesscategory: abc
createtimestamp: 20050709198316x
creatorsname: cn=bulkload
modifiersname: cn=bulkload
modifytimestamp: 20050709198316x
objectclass: top
objectclass: cuser
cquestion: leo210375

ghostdog74 · 09-25-2007, 08:22 PM

you had a similar thread like this few days ago. Read post #18 from that thread. That's how you get user input inside awk.

cmontr · 09-26-2007, 08:14 AM

I really appreciate for the help. I am still trying to figure out why I couldnt make it run. When I run this: awk -f gtest.awk a.txt I get an error ,...perhaps something I did wrong in the script...please have a look if you get a min...I would really appreciate...

code:

awk 'BEGIN{ headingFound = 1;
print "what is cquestion? "
getline choice < "/dev/tty"
}
}

/^cquestion:/ { headingFound = 1; }

/^dn:/ {
if( headingFound == 1 ){
print $2;
headingFound = 0;
}

}

Quote:

Originally Posted by ghostdog74

you had a similar thread like this few days ago. Read post #18 from that thread. That's how you get user input inside awk.

cmontr · 09-26-2007, 08:55 AM

I really appreciate for the help. I am still trying to figure out why I couldnt make it run. When I run this: awk -f gtest.awk a.txt I get an error ,...perhaps something I did wrong in the script...please have a look if you get a min...I would really appreciate...

code:

awk 'BEGIN{ headingFound = 1;
print "what is cquestion? "
getline choice < "/dev/tty"
}
}

/^cquestion:/ { headingFound = 1; }

/^dn:/ {
if( headingFound == 1 ){
print $2;
headingFound = 0;
}

}

Quote:

Originally Posted by ghostdog74

you had a similar thread like this few days ago. Read post #18 from that thread. That's how you get user input inside awk.

firstfire · 09-26-2007, 10:07 AM

Hi, cmontr!

If I understand your question correctly, then you can try this:

Code:

# Why you write /bin/sh here? You could write
#   #!/bin/awk -f
# and run $ chmod +x ctest.awk
# instead to make this script executable

# ctest.awk

BEGIN{
	headingFound = 0;
	print "what is your name?: "
	getline choice < "/dev/tty"
}
/^cquestion:/ { if($2==choice) headingFound = 1; }
/^dn:/ {
	if( headingFound == 1 ){
		print $2;
		headingFound = 0;
	}
}

This will find first occurrence of '^cquestion: <choice>'
and then print first field '^dn: ...' which it found.

Hope this helps.

cmontr · 09-26-2007, 03:24 PM

Hi again, thanks for the help but I am getting error running the script against a file called a.txt.

It indicates:

awk: syntax error near line 5
awk: illegal statement near line 5 --> where this line is as follows:

1 #!/bin/awk -f
2 BEGIN{
3 headingFound = 0;
4 print "what is your name?: "
5 getline choice < "/dev/tty"
6 }
7 /^cquestion:/ { if($2==choice) headingFound = 1; }
8 /^dn:/ {
9 if( headingFound == 1 ){
10 print $2;
11 headingFound = 0;
12 }
13 }

I know all you guys directed as much but still getting some errors as seen. Can you please direct me again? Thanks much.

Quote:

Originally Posted by firstfire

Hi, cmontr!

If I understand your question correctly, then you can try this:

Code:

# Why you write /bin/sh here? You could write
#   #!/bin/awk -f
# and run $ chmod +x ctest.awk
# instead to make this script executable

# ctest.awk

BEGIN{
	headingFound = 0;
	print "what is your name?: "
	getline choice < "/dev/tty"
}
/^cquestion:/ { if($2==choice) headingFound = 1; }
/^dn:/ {
	if( headingFound == 1 ){
		print $2;
		headingFound = 0;
	}
}

This will find first occurrence of '^cquestion: <choice>'
and then print first field '^dn: ...' which it found.

Hope this helps.

firstfire · 09-26-2007, 11:39 PM

Hi!

Maybe the reason is your awk interpreter? Please post the output of `awk --version' as well as your distribution (I use Debian for example and GNU awk 3.1.5). You also can omit '< "/dev/tty"' from call to getline, because it is useless IMO and your awk may not understand redirection. If that did not work you can try getline without arguments, and then assign the value of $0 to choice. And if that will not work... ok, just use BASH features:

Code:

#!/bin/bash
# USAGE: ctest.sh a.txt

echo -n "what is your name?: "
read choice
awk "
BEGIN{
	headingFound = 0;
}
/^cquestion:/ { if(\$2==\"$choice\") headingFound = 1; }
/^dn:/ {
	if( headingFound == 1 ){
		print \$2;
		headingFound = 0;
	}
}
" $1

or try Perl solution.

Good luck!

ghostdog74 · 09-27-2007, 01:28 AM

Quote:

Originally Posted by firstfire

You also can omit '< "/dev/tty"' from call to getline, because it is useless IMO and your awk may not understand redirection.

not really. consider this

Code:

bash-2.03$ more file
line1
line2
line3
bash-2.03$ nawk 'BEGIN{getline  choice}{print $0,choice}' "file"
line2 line1
line3 line1
bash-2.03$ nawk 'BEGIN{getline  choice<"/dev/tty"}{print $0,choice}' "file"
test
line1 test
line2 test
line3 test

if "/dev/tty" is not used, the first $0 is "gobbled" up.
@OP, if your system has nawk, you can try that and see.

cmontr · 09-27-2007, 08:09 AM

I am sorry - I guess you misunderstood.

Script should ask a question when you run, such as:

"What is your vzquestion?" And it would go get the value and print of dn of whenever it finds that cquestion in the txt file from db.

If you can help, that would greatly appreciate it.

Thank you again

------------------

Quote:

Originally Posted by cmontr

Hi again, thanks for the help but I am getting error running the script against a file called a.txt.

It indicates:

awk: syntax error near line 5
awk: illegal statement near line 5 --> where this line is as follows:

1 #!/bin/awk -f
2 BEGIN{
3 headingFound = 0;
4 print "what is your name?: "
5 getline choice < "/dev/tty"
6 }
7 /^cquestion:/ { if($2==choice) headingFound = 1; }
8 /^dn:/ {
9 if( headingFound == 1 ){
10 print $2;
11 headingFound = 0;
12 }
13 }

I know all you guys directed as much but still getting some errors as seen. Can you please direct me again? Thanks much.

firstfire · 09-27-2007, 11:25 PM

Quote:

Originally Posted by ghostdog74

not really.
...
if "/dev/tty" is not used, the first $0 is "gobbled" up.
@OP, if your system has nawk, you can try that and see.

Yes, you right, ghostdog74, sorry.

cmontr, please post some info about your environment, at least version of your awk interpreter. On my system all mentioned scripts work well without error messages and some of them do exactly what you want.

If the reason is in `getline' statement or not, this can be checked simply by using `choice="..."' instead of `getline'.

cmontr · 09-28-2007, 08:02 AM

in my system awk --version doent bring anything ...it is SUN ultra 250 running solaris 5.7 and oracle 9i db. Please let me know what commands you like m to run for a specific information.

firstfire · 09-29-2007, 07:47 AM

Hi!

On this site I found that your version of awk uses very restricted syntax of `getline' statement:

Code:

getline 

Set $0 to the next input record from the current input file. getline returns 1 for successful input, 0 for end of file, and -1 for an error.

.. and there is nothing about redirection (I mean this `<"/dev/tty"').

But there is another man page describing `nawk' (man nawk) which is placed in /usr/bin/nawk or /usr/xpg4/bin/awk. nawk seems to possess all the features we need, so try it.

Anyway you can just pass the variable `choice' to the interpreter:

Code:

$ nawk -v 'choice=...' -f ctest.awk a.txt

and use a shell script to obtain actual value for `choice'.

P.S.: If "/dev/tty" do not work for you, try "/dev/stdin", it should be there I think.