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Need File Name comparison help on Korn Shell Script

I am trying to compare two filenames including the paths. Basically if two paths are similar then my program wants to display message. So I need to check for if two pathnames are same in the sorce and destination. So I was trying for the code to compare tow filename sincluding "\" and if the Parent FIle Path is found in the child file path then I need to displays ome message. I was trying to modify something like this:
#!/bin/ksh
# Sample script

file1="C:\Text\Latest\Article\News.txt"

file2="C:\Text\Latest"

pattern1=$file2

if [[ $file1 = pattern1* ]]
then
echo "Do something"
fi

========================================
Also tried == and $file2 in place of pattern1.

You might try the regular expression match operator:

Code:

#!/bin/ksh

file1="C:\Text\Latest\Article\News.txt"

file2="C:\Text\Latest"



if [[ $file1 =~ $file2 ]]

then

  echo "Do something"

fi

Anyway the backslashes in the file names may confuse the shell which interprets them as escape characters. For this reason it is convenient to change them into a slash or some other character to do the comparison:

Code:

#!/bin/ksh

file1="C:\Text\Latest\Article\News.txt"

file2="C:\Text\Latest"



if [[ ${file1//\\//} =~ ${file2//\\//} ]]

then

  echo "Do something"

fi

Hope this helps.

Well I am not sure why you have copied file2 into pattern1, but ultimately you only made 2 small typos to get your script to work as is:

Code:

#!/bin/ksh

# Sample script



file1="C:\Text\Latest\Article\News.txt"



file2="C:\Text\Latest"



pattern1=$file2



if [[ $file1 = "$pattern1"* ]]

then

    echo "Do something"

fi

Need More Clarification

The approaches suggested do help. But I am trying something like:

##Logic
#Need to copy from one file-path to other file-path
#e.g. from D:\Books\Latest\Novels\Finkler to D:\Books\Latest
#The two string approach would give match even if the destination is only D:\.
#So introduced third string str (which is constant) to check for match with str2 first
#Then compare the fixed path in str3 with str

#! /bin/ksh
str=$1
str2=$2
str3="D:\Books\Latest"
echo $str
echo $str2
if [[ $str2 == [$str3]* ]] then
if [[ $str == [$str2]* ]] then
echo "Go"
else
echo "NoGo1"
fi
else
if [[ $str == [$str3]* ]] then
echo "Go2"
else
echo "NoGo2"
fi
fi

The above code gives me NoGo2 even for matching string.
I am entering arguments as:
D:\Books\Latest D:\Books\Latest\Novels\Finkler

So we should have mentioned before, please use [code][/code] tags to make your code more readable and indented.

As for your code:

1. Make sure arguments are passed to script with single quotes around them to preserve the \ and not allow escaping of next character

2. str3 is same as above and needs single quotes

3. Replace [] around comparisons, ie [$str3]*, with "" as I explained in previous post, ie "$str3"*

4. Without any of the changes above your script fails anyway due to missing semi-colon before each of your 'then' statements

Once these changes are made the result I get is: NoGo1, which appears to be correct based on input.

Quote:

Originally Posted by confusiac437 (Post 4392595)

I am trying to compare two filenames including the paths. Basically if two paths are similar then my program wants to display message.

What do you mean by "are similar"?

If you want to test if string $file1 starts with $file2 or vice versa, use

Code:

if [ "${file1:0:${#file2}}" == "${file2:0:${#file1}}" ]; then

    echo "$file1 starts $file2, or $file2 starts $file1."

fi

If you want the comparison to be case insensitive, use

Code:

typeset -u temp1 temp2

temp1="${file1:0:${#file2}}"

temp2="${file2:0:${#file1}}"

if [ "$temp1" == "$temp2" ]; then

    echo "($file1 prefix) ${file1:0:${#temp1}} and ($file2 prefix) ${file2:0:${#temp}} match."

fi

If you want to find the longest common path prefix, it gets a bit more complicated; especially if you wish to handle symlinks and bind-mounts correctly.

Any alternate approaches

Code:

if [ "${file1:0:${#file2}}" == "${file2:0:${#file1}}" ]; then

    echo "$file1 starts $file2, or $file2 starts $file1."

fi

If you want the comparison to be case insensitive, use

Code:

typeset -u temp1 temp2

temp1="${file1:0:${#file2}}"

temp2="${file2:0:${#file1}}"

if [ "$temp1" == "$temp2" ]; then

    echo "($file1 prefix) ${file1:0:${#temp1}} and ($file2 prefix) ${file2:0:${#temp}} match."

fi

The above approach does not work for me. Am working in Korn Shell on very old version of Unix.What are the other alternatives in case I basically just want to check if one file path contains other file path in it?

Well, I have access to ksh on SunOS 5.10, and for it, case seems to work well:

Code:

FILE1="/path/to/some/file"

FILE2="/path/to"



# +u case sensitive, -u is case insensitive

typeset +u TEMP1 TEMP2

TEMP1="$FILE1"

TEMP2="$FILE2"



case "$TEMP1" in

  "$TEMP2")      echo "FILE1 ($FILE1) is the same as FILE2 ($FILE2)" ;;

  "${TEMP2%/}/"*) echo "FILE1 ($FILE1) has prefix FILE2 ($FILE2)" ;;

esac

case "$TEMP2" in

  "${TEMP1%/}/"*) echo "FILE2 ($FILE2) has prefix FILE1 ($FILE1)" ;;

esac

Note that the above uses ${TEMP%/}/ which literally means the value of TEMP, with the trailing slash removed if there is one, with a trailing slash added. Even old Korn shells should support that expression. (I recommend you check, though.)

You'll want to use that, if you do not want /some/path to match /some/path2/file . Otherwise, just use plain $TEMP .

If you are working on a truly ancient Unix, you can always work around the problems by using wc for length, cut for string manipulation, and optionally tr for case conversion:

Code:

FILE1="/some/path"

FILE2="/some/other/path"



LEN1=`echo -n "$FILE1" | wc -c | tr -cd 0-9`

LEN2=`echo -n "$FILE2" | wc -c | tr -cd 0-9`

if [ $LEN1 -gt 0 ] && [ $LEN2 -gt 0 ]; then

    TEMP1="`echo -n "$FILE1" | tr a-z A-Z | cut -b1-$LEN2`"

    TEMP2="`echo -n "$FILE2" | tr a-z A-Z | cut -b1-$LEN1`"

    if [ ":$TEMP1" == ":$TEMP2" ]; then

        echo "FILE1 ($FILE1) is a prefix of FILE2 ($FILE2) or vice versa."

    fi

fi

The above does case insensitive comparison; if you want case sensitive comparison, just replace the | tr a-z A-Z | above with | .

Old shells don't always support $(cmd) subshells, so I use the ancient but equivalent `cmd` instead.

Note that the lengths are intentionally swapped, so that TEMP1 and TEMP2 end up being the same length. I put the colons into the compared patterns just in case your shell does not compare empty strings properly.