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Shell Programming and Scripting

compare two characters

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# 1  
Old 06-20-2011
compare two characters
how can I compare two characters in shell script?

similar to C++ code:

char ch='a';
if(ch=='a')
{
do_something;
}
# 2  
Old 06-20-2011
Code:
ch="a"
if [ $ch == "a" ]; then
  do_something
fi

This User Gave Thanks to bartus11 For This Post:
bismillah
# 3  
Old 06-20-2011
i have something like this and i get the error: ./proiect: line 19: [: ==: unary operator expected


while read -n1 char; do
if [ $char == "a" ]
then
((i++))
fi

done < file
# 4  
Old 06-20-2011
Use = instead of ==
Code:
if [ "$char" = a ]

This User Gave Thanks to Scrutinizer For This Post:
bismillah
# 5  
Old 06-20-2011
this works perfect,thanks
# 6  
Old 06-20-2011
BASH has == , which can cause some bad habits when many other shells don't.
This User Gave Thanks to Corona688 For This Post:
bismillah
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