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I have a <newline> separated list of files at various websites. eg.

Code:

http://blah.com/thing1.tar.gz

http://blah.com/thing2.tar.gz

I want to write a script to read this list and determine if all these files are in a directory.

I think I can figure out the rest, but I'm having trouble working out a sed statement to take a line of text and remove everything before and including the last forward slash. So I'm just left with a filename.

How about param expansion

Code:

t='http://blah.com/thing1.tar.gz'



 echo ${t##*/}

thing1.tar.gz

http://wiki.bash-hackers.org/syntax/...string_removal

Try this script

Code:

#/bin/bash



while read line

do

if [ -f $(echo ${line##*/}) ]; then echo "${line##*/} exists"

else

echo "${line##*/} does not exists" 

fi

done < list

Replace list with the file of http links

This script will extract the filename from the http link and check the current directory for existence of file or not

Bonus Code with Awk:

Code:

awk -F "/" '{print $NF }' list

Thanks guys, it worked great.

You're welcome mreff555

Mark the thread solved from the threads tool if you feel it was solved.

Quote:

Originally Posted by linuxCode (Post 4977868)

Code:

if [ -f $(echo ${line##*/}) ]; then echo "${line##*/} exists"

Useless Use Of Echo. Just evaluate the expansion directly.

Also, when using advanced shells like bash or ksh, it's recommended to use [[..]] for string/file tests, and ((..)) for numerical tests. Avoid using the old [..] test unless you specifically need POSIX-style portability.

http://mywiki.wooledge.org/BashFAQ/031
http://mywiki.wooledge.org/ArithmeticExpression

If you use single brackets you have to make sure to enclose the string in quotes so that it's properly protected from word-splitting and glob expansion.

And finally, the formatting could be a bit cleaner.

I'd personally write it more like this:

Code:

#/bin/bash



listfile=/path/to/list.txt



while read -r line || [[ -n $line ]]; do



    line=${line##*/}



    if [[ -f $line ]]; then

        echo "$line exists"

    else

        echo "$line does not exist" 

    fi



done < "$listfile"

The extra [[ -n $line ]] test protects against the possibility of the input having no final newline.

Quote:

Originally Posted by linuxCode (Post 4977868)

Try this script

Code:

#/bin/bash



while read line

do

if [ -f $(echo ${line##*/}) ]; then echo "${line##*/} exists"

else

echo "${line##*/} does not exists" 

fi

done < list

Replace list with the file of http links

This script will extract the filename from the http link and check the current directory for existence of file or not

Bonus Code with Awk:

Code:

awk -F "/" '{print $NF }' list

Well that is great & I've saved it with me. Very smart script you've written. Thanks :)))

Quote:

Originally Posted by David the H. (Post 4980137)

Code:

#/bin/bash



listfile=/path/to/list.txt



while read -r line || [[ -n $line ]]; do



    line=${line##*/}



    if [[ -f $line ]]; then

        echo "$line exists"

    else

        echo "$line does not exist" 

    fi



done < "$listfile"

The extra [[ -n $line ]] test protects against the possibility of the input having no final newline.

Thanks David the H. for the bash tips. :)

+1

Quote:

Originally Posted by linuxzilla.com (Post 4980161)

Well that is great & I've saved it with me. Very smart script you've written. Thanks :)))

You're Welcome :)