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Read First Character of Each Line in File

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# 1  
Old 07-11-2007
Read First Character of Each Line in File
I need a better way to read the first character of each line in a file and check if it equals the special character ¤. This character tells me where there is a break in the reports. The file has over 500,000 lines. Currently, this is my code -

if [[ $(echo $line|cut -c1-1) = "¤" ]]
I am using Korn Shell as a scripting language. Is there a better way to do this?

Thank you for your assistance.
# 2  
Old 07-11-2007
I don't know if it will make much difference, but you can try this:
Code:
typeset -L1 mOne
while read mLine
do
  mOne=$mLine
done < input_file

# 3  
Old 07-11-2007
Try:
Code:
if [ ${line:0:1} = '¤' ]
then
  # bingo
fi

Regards
# 4  
Old 07-11-2007
${line:0:1}

works in bash just fine, but not ksh.
# 5  
Old 07-11-2007
Shell_Life's suggestion helped a lot. Processing time went from over 5 hours to 45 minutes. This was the code:

typeset -L1 mOne
while read mLine
do
mOne=$mLine
done < input_file

jim mcnamara was correct that ${line:0:1} would not work.

Thank you for the help.
# 6  
Old 07-11-2007
Quote:
Originally Posted by azelinsk
Quote:
${line:0:1}

works in bash just fine, but not ksh.
jim mcnamara was correct that ${line:0:1} would not work.
I apologize, didn't realise that.

Regards
# 7  
Old 07-11-2007
Quote:
Originally Posted by azelinsk
I need a better way to read the first character of each line in a file and check if it equals the special character ¤. This character tells me where there is a break in the reports. The file has over 500,000 lines. Currently, this is my code -

if [[ $(echo $line|cut -c1-1) = "¤" ]]
I am using Korn Shell as a scripting language. Is there a better way to do this?

Thank you for your assistance.
what do you want to do after you have checked the first character equals something?
Code:
awk  '/^c/{ do something }' file
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