LinuxQuestions.org - Bash script missing matches to conditionals

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Bash script missing matches to conditionals

Code:

#!/bin/bash

SAVEIFS=$IFS

IFS=$( echo -e "\n\b")



 while read -r line; do

        comm1=$(exiftool -fast5 -s -S-Comment "$line")

        echo "Checking $file0."

        if [ ! -z "$comm1" ];then

                echo "$file0 has no comment data. Moving on"

                echo "$file0">>nocomment.txt

        fi

        if [ -n "$comm1" ]; then

                echo "$file0 has Comment data."

                echo -e "$file0^$comm1" >>hascomment.txt

        fi

        if [[ "$comm1" = "Created with GIMP"  ]]; then

                echo -e "$file0 has an unwanted comment. Writing to file."

                echo -e "$file0">>has-bad-comment.txt

                exiftool -fast5 -overwrite_original_in_place -q -P -Comment="$file0"

                echo -e "Comment data removed from $file0."

                echo -e "$file0">>comment-cleared.txt

        fi

        if [[ "$comm1" = "CREATOR: gd-jpeg v1.0 (using IJG JPEG v62), quality =100." ]];then

                echo -e "$file0 has an unwanted comment. Writing to file."

                echo -e "$file0">>has-bad-comment.txt

                exiftool -fast5 -overwrite_original_in_place -q -P -Comment="$file0"

                echo -e "Comment data removed from $file0."

                echo -e "$file0">>comment-cleared.txt

        fi

        

done<commented-files.txt

IFS=$SAVEIFS

I've run it on batches of files where either or both of those strings were in more than one JPEG comment. I've even put them in some JPEGs myself with Exiftool to make them more 'conspicuous.'

The questions are:
Where am I making it skip returning the tip-offs to stdout? Or the 'remove' command from Exiftool ('-Comment=' with a null value is equivalent to a 'delete' or -M"del {exiv2} command.)

Carver

Quote:

Originally Posted by L_Carver (Post 5632329)

I call it "badcommentcheck." It uses Exiftool to find and remove what I consider unnecessary strings in the JPEG comment header of files of that type. As it is now, it neither alerts the user when it finds them nor removes them with Exiftool silently when it does.

The code looks like this. (BTW, shellcheck missed the mistakes --if there are any -- with the 'alerts' altogether)

I've run it on batches of files where either or both of those strings were in more than one JPEG comment. I've even put them in some JPEGs myself with Exiftool to make them more 'conspicuous.'

The questions are:
Where am I making it skip returning the tip-offs to stdout? Or the 'remove' command from Exiftool ('-Comment=' with a null value is equivalent to a 'delete' or -M"del {exiv2} command.)

Carver

Without your data files, I can't run this myself and get the same results, but I can provide tip: have you tried running the script with tracing? Add -xv after the bash in your first line, or invoke it

Code:

bash -xv badcommentcheck

That will show you exactly what bash is doing.

Also, the code is incomplete as the variable 'file0' is never set. So as above, please provide example files and try the debugging option offered.

Quote:

Originally Posted by L_Carver (Post 5632329)

Code:

        if [ ! -z "$comm1" ];then

                echo "$file0 has no comment data. Moving on"

                echo "$file0">>nocomment.txt

        fi

That says, "If $comm1 is not zero-length, then the file has no comment data." Seems backwards to me.

Maybe he got it confused with -n, or read the wrong thing somewhere. It's in single brackets, I'm wondering if maybe he meant to do

Code:

if [ ! "$comm1" ]; then

Looks to me like the big problem is the lack of a space between "-S" and "-Comment"

Code:

comm1=$(exiftool -fast5 -s -S-Comment "$line")

# should be

comm1=$(exiftool -fast5 -s -S -Comment "$line")

Without that space, nothing is returned, making it appear that no files have any comment (probably why the test got reversed to stop that darn "no comment data" message for every file).

you might want to re-NULL your variable too while you're at it. When it gets done checking one file to the next to clean it out.

before you're checking

Code:

comm1=''

comm1=$(exiftool -fast5 -s -S -Comment "$line")

        echo "Checking $file0."

        if [ ! -z "$comm1" ];then

then remove your ! in that code, because you're checking for NULL not NOT NULL
with the -z

Code:

comm1=''

comm1=$(exiftool -fast5 -s -S -Comment "$line")

        echo "Checking $file0."

#if NULL empty then 

        if [ -z "$comm1" ];then

            echo "$file0 has no comment data. Moving on"

            echo "$file0">>nocomment.txt

        fi

example

Code:

if [ -z "$1" ]; then

    echo "Empty Variable 1"

fi





if [ -n "$1" ]; then

    echo "Not Empty Variable 2"

fi

If statments could be changed too

Code:



#!/bin/bash

SAVEIFS=$IFS

IFS=$( echo -e "\n\b")



#Changing your first set of if statements to this.



 while read -r line; do

        

        comm1=$(exiftool -fast5 -s -S -Comment "$line")

        echo "Checking $file0."

        if [ ! -z "$comm1" ];then

                echo "$file0 has no comment data. Moving on"

                echo "$file0">>nocomment.txt

        else

                echo "$file0 has Comment data."

                echo -e "$file0^$comm1" >>hascomment.txt

        fi



        # the logic behind that was if it is not empty 

          then it has to have something in it, so we 

          use the else instead of another test. Cutting 

          down on time needed to check everything. Causing 

          a faster run. 

        

        

#changing your second if statements to this. 

        

        if [[ "$comm1" = "Created with GIMP"  ]]; then

                echo -e "$file0 has an unwanted comment. Writing to file."

                echo -e "$file0">>has-bad-comment.txt

                exiftool -fast5 -overwrite_original_in_place -q -P -Comment="$file0"

                echo -e "Comment data removed from $file0."

                echo -e "$file0">>comment-cleared.txt

        else



          if [[ "$comm1" = "CREATOR: gd-jpeg v1.0 (using IJG JPEG v62), quality =100." ]];then

                echo -e "$file0 has an unwanted comment. Writing to file."

                echo -e "$file0">>has-bad-comment.txt

                exiftool -fast5 -overwrite_original_in_place -q -P -Comment="$file0"

                echo -e "Comment data removed from $file0."

                echo -e "$file0">>comment-cleared.txt

          fi

        fi

        

done<commented-files.txt

IFS=$SAVEIFS

only the if statements were changed in this example.

compound statements