topic Re: Directory check in Operating System - Linux

Directory check

Unix or Linux? — Fri, 06 Oct 2006 10:18:59 GMT

How do I check for the existence of a directory?

Basically what I would like to do is the user inputs a name, then a script checks whether the directory exist. If it does not exist then create the directory and subdirectories. Also chmod -R 777. The script should be able to check this from any directory that it is run from.

Re: Directory check

Patrick Wallek — Fri, 06 Oct 2006 10:34:15 GMT

Something like this:

#!/usr/bin/sh
echo "Enter Dir Name: "
read DIRNAME
if [[ -d ${DIRNAME} ]] ; then
echo "Dir Exists"
else
echo "Dir does not exist"
mkdir ${DIRNAME}
chmod 770 ${DIRNAME}
fi

You notice I didnot chmod 777. 777 are VERY VERY VERY BAD permissions. That means that ANYBODY on the server can royall screw up anything in that directory.

Re: Directory check

Yang Qin_1 — Fri, 06 Oct 2006 10:37:15 GMT

First of all, to grant directories with 777 is really not secure and you use at least 775?

Secondly, user input must contain full path otherwise you won't know where to start with

#!/usr/bin/ksh

ls -l $1
if [ $? -eq 0 ] ; then
echo $1 " exists"
else
mkdir -p $1
chmod -R 777 $1
echo $1 " has been created"
fi

exit

call it dirchk.sh

user need to run it like "dirchk.sh /aaa/bbb/ccc"

Re: Directory check

A. Clay Stephenson — Fri, 06 Oct 2006 10:40:36 GMT

It's rather simple:

#!/usr/bin/sh

typeset DNAME=""
typeset STAT=255
echo "Enter directory name: \c"
read DNAME
if [ -e "${DNAME}" ]
then
echo "${DNAME} already exists.] >&2
else
mkdir "${DNAME}"
STAT=${?}
if [ ${STAT} -ne 0 ]
then
echo "Cannot mkdir ${DNAME}; status ${STAT}." >72
fi
exit ${STAT}

I have no idea what the subdirectories should be. It should be obvious where your chmod goes but setting mode to 777 should be done only in extremely rare cases; it is a huge security hole.

Re: Directory check

Peter Nikitka — Sat, 07 Oct 2006 15:05:05 GMT

Hi,

if you use

umask 0
mkdir -p -m 777 dirname

you will get all you need (whether it makes sense to have world writable directories or not).
In this form you will
- not get an error message for existing directories
- an error message if the creation failes
- the exit status will be accordingly

mfG Peter

Re: Directory check

Unix or Linux? — Tue, 10 Oct 2006 11:05:50 GMT

Another small issue: I need the directory to be created all in lowercase. So if the user enters DIR123 the directory will be created as dir123 if the directory does not already exist.

I have tried using the tr command to no success as follows.

LUsr=`echo $DIRNAME | tr'[:upper:]''[:lower:]'`

What am I doing wrong here?

I also tried the following:

LUsr=`nawk '{print tolower($DIRNAME)}'`

Re: Directory check

Sandman! — Tue, 10 Oct 2006 11:30:47 GMT

Instead use the commands below...

# echo $DIRNAME | tr [:upper:] [:lower:]

OR

LUsr=`echo $DIRNAME | nawk '{print tolower($0)}'`

cheers!

Re: Directory check

James R. Ferguson — Tue, 10 Oct 2006 12:06:56 GMT

Hi:

If you are collecting your data interactively, use 'typeset -l' to lowercase your input:

# typeset -l NAME
# read NAME
# echo ${NAME}

Regards!

...JRF...

Re: Directory check

Unix or Linux? — Thu, 12 Oct 2006 08:20:32 GMT

thanks