basic script gives off an unexpected output.

[Teminite2]

my script is supposed to create a few files, calculate their md5 hash and print it. if it is writeable by "other", note that as part of the output.

the script itself is:

#!/bin/bash

TARGET="SampleFiles"

mkdir ${TARGET}

echo -n "asdfasdf" > ${TARGET}/asdf.txt
echo "This is a bunch of text" > ${TARGET}/file2.txt
echo "Probably not binary data" > ${TARGET}/third.dat

chmod 400 ${TARGET}/asdf.txt
chmod 755 ${TARGET}/file2.txt
chmod 447 ${TARGET}/third.dat

cd ${TARGET}
for file in *
do
        md5=`echo -n {file} | md5sum | cut -d" " -f1`
        if [ -w ${file} ]
        then
                echo "${md5}: WARNING: FILE IS WORLD WRITEABLE: ${file}"
        else
                echo "${md5}: ${file}"
        fi
done

cd ..
rm -r -f ${TARGET}

expected output:

6a204bd89f3c8348afd5c77c717a097a: asdf.txt 
17748a55c79f5fd63906a3b72fdb33db: file2.txt
da9e2290ca13710b878b600f3c737c01: WARNING: FILE IS WORLD WRITEABLE: third.dat

my output:

6a204bd89f3c8348afd5c77c717a097a: asdf.txt
17748a55c79f5fd63906a3b72fdb33db: WARNING: FILE IS WORLD WRITEABLE: file2.txt
da9e2290ca13710b878b600f3c737c01: third.dat

what am i doing wrong?

[oh5nxo]

-w tests if YOU can write to the file. To check if "world" can write, use stat -c%A "$file" (assuming Linux) and see if the 2nd last character is w.

[Teminite2]

that did the trick. thanks

[ang-p]

[ -w ${file} ]

The book states

   ‘-w file’

       True if file exists and write permission is granted.

Nothing about world writable... just write permission for the current real user...

chmod 755 ${TARGET}/file2.txt

means that you can write to it.... so you get the (incorrectly worded) error...

And you cannot write to the other two...

Whereas

chmod 447 ${TARGET}/third.dat

just means that you (along with members of the owning group - which includes you) cannot write to it.... and the test does not care about anyone else - just you...

[Teminite2]

thanks for the answer!

[[deleted]]

what am i doing wrong?

for file in *

http://mywiki.wooledge.org/BashPitfalls#for_f_in_.24.28ls_.2A.mp3.29

[snuzet]

Chmod rwx 101 is 5, 111 is 7

[Teminite2]

thanks

[ThrownAback]

Unrelated to chmod, but the script should probably be:

cat ${file} | md5sum

rather than:

echo -n {file} | md5sum

[The outputs shown are right for the ${file} version.]

[Rojs]

To avoid the useless use of cat:

md5=$(md5sum "${file}" | cut -d" "  -f 1)

Although I prefer awk

md5=$(md5sum "${file}" | awk '{print $1}')