Reading a file line by line and processing for each line

sagarparadkar · #1 (**permalink**) 02-24-2009

Hi,

I am a beginner in shell scripting. I have written the following script, which is supposed to process the while loop for each line in the sid_home.txt file. But I'm getting the 'end of file' unexpected for the last line. The file sid_home.txt gets generated as expected, but the script doesn't execute the instructions in the while loop:

#!/bin/ksh
cd /home/dba/utils/scripts/monitor
sed '/^#.*$/d' /var/opt/oracle/oratab | sed '/^[Cc]lient.*$/d' | sed '/^CRS.*$/d' | awk -F: '{print$1, $2;}' > sid_home.txt
{ while read LINE;do
ORACLE_SID=`awk '{print $1;}' $LINE`; export ORACLE_SID
ORACLE_HOME=`awk '{print $2;}' $LINE`; export ORACLE_HOME
DATE_TIME=`date +%m%d%y%a_%H%M`; export DATE_TIME
TSPALERT_LOG=tspalert_${ORACLE_SID}_${DATE_TIME}.log;export TSPALERTLOG
ORACLE_BASE=${ORACLE_HOME}; export ORACLE_BASE
ORACLE_BIN=${ORACLE_HOME}/bin; export ORACLE_BIN
LD_LIBRARY_PATH=/usr/openv/netbackup/bin:/usr/dt/lib:/usr/openwin/lib:/usr/local/lib:${ORACLE_HOME}/lib32
LD_LIBRARY_PATH_64=${ORACLE_HOME}/lib
ORACLE_DOC=${ORACLE_HOME}/orainst/doc
${ORACLE_HOME}/bin/sqlplus -s /nolog << EOF
set heading off
spool $TSPALERT_LOG;
select name from v$database;
select to_char(sysdate,'DD-MM-YYYY HH24:MI:SS') from dual;
select tablespace_name,sum(bytes)/1048576 MBUsed, sum(maxbytes)/1048576 TotalMB, sum(bytes)/sum(maxbytes)*100 PercentUsed
from dba_data_files
group by tablespace_name
having sum(bytes)/sum(maxbytes)*100 >= 80;
spool off
EXIT;
EOF
if [ -f ${TSPALERT_LOG} ]; then
echo "**ERROR**: TABLESPACE NEARLY FULL OR NOT ENOUGH ROOM FOR THE NEXT EXTENT IN ${ORACLE_SID}. Check log ${TSPALERT_LOG} " > /dev/null
mv ${TSPALERT_LOG} ${TSPALERT_LOG}.old > /dev/null
fi
done } < sid_home.txt

adderek · #2 (**permalink**) 02-27-2009

Beginner? This is one of the better ksh codes that I have seen. And believe me - I have seen plenty od it.
Some hints that might help you:
- Try enclosing variables with quotes: variable="${var}" (the way you are using could work fine but under some circumstances you can get into problems - an example is when ${var} is equal to 'some text with $trange characters').
- I'm not sure if there is a need to enclose that function within brackets - if I remember correct you should be able to "print" the file into the loop without brackets
- Send this sid_home.txt file and make sure that the problem is not related to end of line characters (unix/max/windows format) - if you send it then I could take a look onto it
- Use tabulation - this code you have sent is not very readable
- You might try the alternative syntax as well (might be worth giving a try): cat "${file}" | while $(read LINE);do ... done
- Execute your code with "set -x;set -v" and check the output. You might try some debuggers as well.

cfajohnson · #3 (**permalink**) 02-27-2009

Quote:

Originally Posted by adderek

Beginner? This is one of the better ksh codes that I have seen. And believe me - I have seen plenty od it.

You must be joking! It's extremely inefficient and poorly written code.

Quote:

Some hints that might help you:
- Try enclosing variables with quotes: variable="${var}" (the way you are using could work fine but under some circumstances you can get into problems - an example is when ${var} is equal to 'some text with $trange characters').

It is never necessary to quote the assignment of one variable to another; it doesn't matter what the variable contains. It only needs to be quoted when there is a literal space in the assignment:
Code:
x='the quick brown fox' ## Quotes necessary for literal spaces
var=$x  ## No quotes necessary

Quote:

- I'm not sure if there is a need to enclose that function within brackets - if I remember correct you should be able to "print" the file into the loop without brackets

There's no need, but it doesn't hurt.

Quote:

- Send this sid_home.txt file and make sure that the problem is not related to end of line characters (unix/max/windows format) - if you send it then I could take a look onto it

Why? All that's needed is to look at the file with od -c and look for \r characters.

However, it would help to post a few lines of the file so we can see what the input to the loop contains.

It should contain a list of filenames, since $LINE is being used as a filename argument to the (probably unnecessary) awk commands.

Quote:

- Use tabulation - this code you have sent is not very readable

I think you mean indentation. That's always good, and more importantly, code posted to this forum should always be enclosed in [code] tags.

Quote:

- You might try the alternative syntax as well (might be worth giving a try): cat "${file}" |

Why would you use cat? It cannot make any difference.

Quote:

while $(read LINE);do ... done

What do you think while $(read LINE) does?

The assignment to LINE only lasts for the duration of the subshell inside $( ... ); it will not be available to the rest of the script.

In other words, it does nothing.

Quote:

- Execute your code with "set -x;set -v" and check the output. You might try some debuggers as well.

adderek · #4 (**permalink**) 02-27-2009

Quote: