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Ignore lines in Shell Script

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# 1  
Old 04-18-2012
Ignore lines in Shell Script


I have a shell script, which reads a *.txt file - line by line. In this text file, I have some lines beginning with "#" that I want to ignore :

#blah blah blah 1
blah blah blah 2
blah blah blah 3
#blah blah blah 4

I want my script to read only the following lines and process them:
blah blah blah 2
blah blah blah 3

Is there a way to incorporate this in my shell script?

[ $# -eq 0 ] && { echo "Usage: $0 <filename>"; exit 1; }
while read line 
done <  "$MY_FILE"

# 2  
Old 04-18-2012
Check if the first character is # and if so, ignore the line.

while read LINE
        [ "${LINE:0:1}" = "#" ] && continue


This syntax should work in bash and ksh.
# 3  
Old 04-18-2012

Works like a charm!
# 4  
Old 04-18-2012
Alternatively you could strip out lines starting with a pound sign before feeding them to the while loop:


grep -v "^#" $MY_FILE | while read LINE
  echo $LINE

exit 0

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