Issue when doing a loop

Thread Tools Search this Thread
Top Forums UNIX for Beginners Questions & Answers Issue when doing a loop
# 1  
Old 06-25-2019
Issue when doing a loop


I just have started learning shell scripting (sh). Why do i only get the date?

while read dt
   echo "Date : ${dt}
   sed -n '/${dt}/,/${dt}/p' file1.log | grep -w ERROR
done < date1.dat

INPUT - date1.dat
2019-04-05 04:58:25
2019-04-05 04:58:26
2019-04-05 05:00:56
2019-04-05 05:08:26
2019-04-05 05:14:08
2019-04-05 05:21:26
2019-04-05 05:31:08

Desired Output
Date : 2019-04-05 04:58:25
2019-04-05 04:58:25,696 [Timer-7] ERROR :  421 Exceeded allowable connection time, disconnecting.

Actual Output
Date : 22019-04-05 04:58:25
Date : 22019-04-05 04:58:26
Date : 22019-04-05 05:00:56
Date : 22019-04-05 05:08:26
Date : 22019-04-05 05:14:08
Date : 22019-04-05 05:21:26
Date : 22019-04-05 05:31:08

Moderator's Comments:
Mod Comment
Please wrap all code, file, input & output/errors in CODE tags
It makes it easier to read and preserves spacing for indenting code or fixed-width data

Last edited by rbatte1; 07-08-2019 at 07:09 AM..
# 2  
Old 06-25-2019
The sed does not find anything.
Your mistake is the 'ticks' around $dt, but the shell only expands $dt within "quotes".
Further, a /x/,/x/ range is always one line, so you can simply address it with one /x/.
Further, consider searching only at the beginning of the lines, by means of /^x/, here /^$dt/ or /^${dt}/
Further, you can save the invocation of grep.
sed -n "/ERROR/!d; /^$dt/p" file1.log

sed "/ERROR/!d; /^$dt/!d" file1.log

Note: in bash you need to turn off history substitution with comand set +H.
This User Gave Thanks to MadeInGermany For This Post:
# 3  
Old 06-25-2019
Thank you MadeInGermany.
Do i always need to turn off history substitution?
# 4  
Old 06-25-2019
Only in an interactive bash shell (i.e. the command line), an exclamation mark followed by an alphanumeric character does history substitution.
For example
echo "!1"

prints line 1 from the command history.
Fortunately a bash script never does history substitution; a set +H work-around is not needed there.
This User Gave Thanks to MadeInGermany For This Post:
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Issue with for loop

Hi Team, I have for loop in my shell script. Which basically loop through all files in the directory, When some files are in the directory it works just fine. But if there are no files at all..still the for loop try to execute. Please help. Below is the code. #!/bin/ksh echo "Program... (5 Replies)
Discussion started by: bharath561989
5 Replies

2. Shell Programming and Scripting

Issue with while loop?

Hi, I have prepared a script to search for backup file information on the Linux server. Script works fine for the most part except the echo statement inside an IF conditional block displays the message ''snapshot directory not found on xxxxx" even though the .snapshot directory is found a... (11 Replies)
Discussion started by: svajhala
11 Replies

3. Shell Programming and Scripting

While Loop issue

Hi, i=0 t5=6000001 while do i=`expr $i + 1` t5=`expr $t5 + 1` echo $t5 done I am able to increment "col3" value but unable to get col1,col2 value. Input: t1=10001 t2=abc t3=ghkc (5 Replies)
Discussion started by: onesuri
5 Replies

4. Shell Programming and Scripting

Issue with using While loop

Hi, I am trying to move a file from remote server to local server and when the transfer completes successfully i call a script in remote server to remove the file which was successfully transferred. I do this by first getting the list of file in remote server and move the text file to local... (8 Replies)
Discussion started by: funonnet
8 Replies

5. Shell Programming and Scripting

for-while loop issue

sup experts..i had a script which was bugging me..was hoping someone could point out the issue here Input file: space separated 2 columns I wanted to print out the 2 columns after assigning them to variables ( bascially the same output but iterate through line by line ). The code worked... (7 Replies)
Discussion started by: foal_newbie
7 Replies

6. Shell Programming and Scripting

until loop issue.

Hi, my script is waiting for 3 files to come to a folder for 30 min but even when all the files arrive in the folder it's still waiting for these three files. Files can come with in 2 min and I want it to start processing them immediately after all the files arrive in the folder. until ; do... (3 Replies)
Discussion started by: gurpartap
3 Replies

7. Shell Programming and Scripting

loop issue

function ext { echo "THANKS & WELCOME BACK" } function upc { echo "TO EXPORT UPROC GIVE UPROC NAME PER LINE IN THE input.txt and PRESS Y" echo "TO GO BACK PRESS 99" read parm0 if ; then start elif ; then for i in `cat input.txt` ; do echo $i $UXEXE/uxext upr upr=$i... (0 Replies)
Discussion started by: kojo
0 Replies

8. Shell Programming and Scripting

loop issue

I have 2 files one of them has all the all mac addresses and the other one has all the ip addresses. Basically, I want to loop thru those 2 files and generate a configuration like below: host { hardware ethernet 00:13:72:3B:B4:3A; fixed-address; }... (4 Replies)
Discussion started by: kkkk
4 Replies

9. Shell Programming and Scripting

while loop issue

Hi, Following is my code and the file FILE_LIST_EXCESS.txt has 40 file names in it while read LineIn do echo ${LineIn} `ftp -vin << END_INPUT >> ${PID}_DS_GET_Log.log 2>&1 open servername user userid password cd FileDir get ${LineIn} END_INPUT`... (4 Replies)
Discussion started by: mgirinath
4 Replies

10. Shell Programming and Scripting

Help With A For Loop Issue

I was wondering how I can modify this for loop, so it only loops through the filenames that do not have an ".old" extension. for filename in $(ls "$1") do echo $filename | grep '\.old$' > /dev/null if then mv $1/$filename $1/$filename.old fi done (5 Replies)
Discussion started by: ralts01
5 Replies
Login or Register to Ask a Question

Featured Tech Videos