Script to accept Multi line inputs

UNIX for Beginners Q & A
1

Hi there,

I'm trying to create a script that will accept multiple inputs by copying and pasting the strings from a notepad, hit Enter key and output the string to a text file.I'm thinking of using the read command however it will just simply get the first line.

Apologies but got no idea how to start with.

Regards,
Norbie

2

Why not read the file directly from your script?

while read x
do
    process $x
done < /path/to/file.txt
3

Please post what you have and what went wrong.

Seems like s/he rather meant

while read x
  do  echo $x >textfile
  done
4 
while IFS= read -r line
do
  printf "%s\n" "$line"
done > outfile

Finish the input by entering CTRL-D

5

Thank you for your help however these codes seem to work only when copying and pasting one by one.

echo "Enter string and hit Ctrl + D"
while IFS= read -r line
do
printf "%s\n" "$line"
done > tmp.log

for b in $(cat tmp.log)
do

find archive*/IT | xargs grep -l $b > count.log
VAR1="$(awk -F/ '{print $0}' count.log)"
echo "$b $VAR1"
done

I'm trying to create a scripts that will accept the following strings, search for it in a given directory and output the results.
Sample Input:

89234500
89234501
89234502

Sample Output:

89234500 ./archive02/IT/0012456.log
89234501 ./archive02/IT/0012457.log
89234502 ./archive02/IT/0012458.log

When I tried to copy the whole string inputs, this is what I got and not responding to Ctrl + D.

$ search.sh
Enter input and hit Ctrl + D








89234502

Appreciate your help on this. Thank you

6

You could do something like this. Put all the input in a file and grep using the file.

[user@host ~]$ cat file
89234500
89234501
89234502
[user@host ~]$ grep -f file -r archive*/IT/*
archive02/IT/0012456.log:89234500
archive02/IT/0012457.log:89234501
archive02/IT/0012458.log:89234502
[user@host ~]$
7

How about splitting the scipt into several blocks and executing them one by one so people (including you!) can tell WHAT goes wrong WHERE?

  • Is the tmp.log file created as expected?
  • Is the for loop executed for the contents of tmp.log?
  • Does the find commend supply its expected results?
  • Is the count.log file populated correctly?
  • Is the VAR1 variable created as expected (I guess, not, as the awk command substitution is quite pointless!)?
8

You have an error in your assessment of the problem: what you want is NOT "multiline input" but in fact you want your input one line at a time and work on each line separately. That is, if your input is:

line1
line2
line3
..

you first want to process "line1", then "line2" and so forth, yes?

You achieve this by reading one line at a time (the "echo" stands for any arbitrary processing you might want to do, replace it with a code block that does what you really want to do):

while read INPUT ; do
     echo "= $INPUT ="
done

Now save this to a file "script.sh" and call it this way:

$ ./script.sh < /path/to/input.file

and you will see the content of the file, one line at a time, but surrounded by equal signs (the proof that the script really has read and processed your file).

Note that it is good style to first "correct" the input: trim leading/trailing blanks, tabs, empty lines, maybe filter out comment lines. Suppose your input file looks like this:

# lines from project A
line-1
    line-2
# line-3   # obsolete

# lines from project B
line-4     
 line-5

What you probably want to process in fact is this:

line-1
line-2
line-4
line-5

therefore, refine your script like this ("<b>" is a literal blank, "<t>" a tab):

sed 's/#.*//;s/^[<b><t>]*//;s/[<b><t>]*$//;/^$/d' |\
while read INPUT ; do
     echo "= $INPUT ="
done

I hope this helps.

bakunin