Shell Script - For and IF issue

[Fefers]

Hello experts..

I'm trying to copy a file the same way that it is, but when it find a NULL character, must input another value.

eg (what I need).

File1.txt

80

80

80

File2.txt

80

100

80

80

Whats going on

Scipt:

for i in File1.txt ;
do
     if [ `cat File1.txt` == "" ]
     then
            echo "100" >> File2.txt
     else
            cat File1.txt >> File2.txt 
     fi
done

# cat File1.txt
80

80

80

# sh -x test.ksh

+ cat File1.txt
+ [ 80 80 80 == ]
test.ksh[5]: 80: 0403-012 A test command parameter is not valid.
+ cat File1.txt
+ 1>> File2.txt

#cat File2.txt
80

80

80

Could some help me please?

[Dennis Handly · Accepted solution]

If you want to read File1.txt and copy all but empty lines to File2.txt, then you need to use a while vs for loop:

while read line; do

   if [ "$line" = "" ]; then  # Note only one "="
      echo "100"
   else
      echo "$line"

   fi
done < File1.txt > File2.txt

[Fefers]

Thanks Dennis and Steven!!

it worked!!

[Dennis Handly]

>Thanks Dennis and Steven!!

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