BASH: Grepping/sedding/etc out part of a file... (from one word to 'blank' line)

Shell Programming and Scripting
1

I have a file that lists data about a system. It has a part that can look like:

the errors I'm looking for with other errors:

Alerts
 Password Incorrect
 Login Error
 Another Error
 Another Error 2
 
Other Info

or, just the errors I need to parse for:

Alerts
 Password Incorrect
 Login Error
 
Other Info

or, if no alerts:

 
Other Info

What I need to do is parse the file, and branch iff the error "Password Incorrect" or "Login Error" comes up. If those come up with other errors that is fine. The file doesn't always include errors (actually this is usually the case). Also, what makes this difficult for me is the line after the last alert isn't blank -- it actually contains a single space.

I have code for it, but it's getting messier and messier, and I'm sure you guys help me out with something WAY more elegant.

Thanks,
Eric

2

can you post your code?? so that we can suggest some change in that code only..

3

I have some thoughts by using sed, tr, awk, etc...
But, cannot put to paper without seeing more of the input data and also what you are trying to get as output.

4

[LEFT]more of the input would look something like:

Time
 12:34 PM

Alerts
 Password Incorrect
 Login Error
 Another Error
 Another Error 2
 
Other Info
 Memory Status 12
 CPU Status 12.44

Bandwidth
 SATA 57%
 ATA 12%

Processes
 Process  Memory CPU
 AAA      12.4GB 34%
 BBB      8.4GB  17%

[/LEFT]

5 
> sed "s/^[A-Z]/~&/" file110 | tr "\n" "|" | tr "~" "\n" | egrep "^Alerts|^Other Info" | tr "|" "\n"
Alerts
 Password Incorrect
 Login Error
 Another Error
 Another Error 2
 

Other Info
 Memory Status 12
 CPU Status 12.44

file110 is simply the log file I copied your sample to
the first sed marks the major headings
then convert new-lines to | (as delimiter)
force new-lines before major headings
grep for either of two major headings
convert the | back to new-lines

6 
awk '/^Alerts/,/^Other Info/' myfile >myfile1
sed 'N;$!P;$!D;$d' myfile1 > myfile2
sed '1d' myfile2 > myfile3
if [[ `cat myfile3 | grep -E 'Password Incorrect|Login Error'` ]]
then
     DO CODE HERE
fi
7 
> if [[ `awk "/^Alerts/,/^Other Info/" file110 | egrep "Password Incorrect|Login Error"` ]] ; then echo "Do this"; fi
Do this
>
8

try this

var1=`sed -ne '/Alerts/{
N
/Password Incorrect/!d
}
/Alerts/,/Other Info/p
' filename`

var2=`sed -ne '/Alerts/{
N
/Login Error/!d
}
/Alerts/,/Other Info/p
' filename`
if [ "$var1" -a "$var2" ]
then
DO CODE HERE
fi
9

Thanks. Real slick. Much easier to read and understand too.

10

you understood the code fully right??