Bash - create a nonexistent directory - bash

I have catalogs
site_2021-11-09_0
site_2021-11-09_1
site_2021-11-09_2
site_2021-11-09_3
site_2021-11-09_4
site_2021-11-09_5
site_2021-11-09_6
I need to add next directory that does not exist, which is site_2021-11-09_7. I need to write a script on loops. How can this be done?
I currently have
#!/bin/bash
date="$(date +%F)"
site="site"
i="0"
while [ ! -d ${site}_${date}_$i ]
do
echo ${site}_${date}_$i
mkdir ${site}_${date}_$i
i=$(( $i + 1))
done
but it doesn't work. If no directories exist, it works forever. If there is directory site_2021-11-09_0, it doesn't work at all. How to understand it logically?

Here are some ways to achieve what you want:
i=0; while [ -d "${site}_${date}_$i" ]; do ((i++)); done; mkdir -v "${site}_${date}_$i"
i=0; while ! mkdir "${site}_${date}_$i"; do ((i++)); done
i=0; for d in "${site}_${date}_"*; do ((i=i>${d##*_}:i?${d##*_})); done; mkdir -v "${site}_${date}_$((i+1))"
when your directories are sortable, that is only when the index counter has a fixed amount of digits, (e.g. ${site}_${date}_001, ${site}_${date}_002 , ... , ${site}_${date}_078), you can make use of the lexicographical ordering of globs
dirlist=( "${site}_${date}"_* )
mkdir -v "${site}_${date}_$(printf "%.3d" "$((10#${dirlist[-1]##*_}+1))")"

Presently your code is doing
while (directory does not exist)
do stuff
but your first directory site_2021-11-09_0 does indeed exist. So the condition inside the while is never satisfied and so the program doesn't run. You can make a slight modification to your code by changing the logic to keep running as long as the directory exists and then make a new directory with the next index when the loop is broken
#! /bin/sh
date="$(date +%F)"
site="site"
i="0"
while [ -d ${site}_${date}_$i ]
do
echo ${site}_${date}_$i
i=$(( $i + 1))
done
mkdir ${site}_${date}_$i

You can use this bash script:
#!/bin/bash -e
prefix=${1:?no site given}_$(date +%F)_
while [[ -d "$prefix$((i++))" ]]; do :; done
mkdir "$prefix$((i-1))"
Call like ./mk-site-dir sitename.
You can hardcode sitename if you want.

As #kvantour says, you currently make a directory so long as it doesn't exist, and then increment i. Thus in any empty directory it will run indefinitely; whereas if there is a matching dir after 0 your code will make all the directories before it and then stop. What you want is probably:
while [ -d ${site}_${date}_$i ]
do
i=$(( $i + 1))
done
mkdir ${site}_${date}_$i
I.e. get the first directory which doesn't exist, and then make it.

Related

Bash simple script copying files to specific folder + renaming to todays effective date

Good day,
I need your help in creating next script
Every day teacher uploading files in next format:
STUDENT_ACCOUNTS_20200217074343-20200217.xlsx
STUDENT_MARKS_20200217074343-20200217.xlsx
STUNDENT_HOMEWORKS_20200217074343-20200217.xlsx
STUDENT_PHYSICAL_20200217074343-20200217.xlsx
SUBSCRIBED_STUDENTS_20200217074343-20200217.xlsx
[file_name+todaydatetime-todaydate.xlsx]
But sometimes a teacher is not uploading these files and we need to do manual renaming the files received for the previous date and then copying every separate file to separate folder like:
cp STUDENT_ACCOUNTS_20200217074343-20200217.xlsx /incoming/A1/STUDENT_ACCOUNTS_20200318074343-20200318.xlsx
cp STUDENT_MARKS_20200217074343-20200217.xlsx /incoming/B1/STUDENT_ACCOUNTS_20200318074343-20200318.xlsx
.............
cp SUBSCRIBED_STUDENTS_20200217074343-20200217.xlsx /incoming/F1/SUBSCRIBED_STUDENTS_20200318074343-20200318.xlsx.
In two words - taking the files from previous date copying them to specific folder with a new timestamp.
#!/bin/bash
cd /home/incoming/
date=$(date '+%Y%m%d')
previousdate="$( date --date=yesterday '+%Y%m%d' )"
cp /home/incoming/SUBSCRIBED_STUDENTS_'$previousdate'.xlsx /incoming/F1/SUBSCRIBED_STUDENTS_'$date'.xlsx
and there could be case when teacher can upload one file and others not, how to do check for existing files?
Thanks for reading that, if you can help me i will ne really thankful - you will save plenty of manual work for me.
The process can be automated completely if your directory structure is known. If it follows some kind of pattern, do mention it here.
For the timing, this maybe helpful:
Filename "tscp"
#
# Stands for timestamped cp
#
tscp() {
local file1=$1 ; shift
local to_dir=$1 ; shift
local force_copy=$1 ; shift
local current_date="$(date '+%Y%m%d')"
if [ "${force_copy}" == "--force" ] ; then
cp "${file1}" "${to_dir}/$(basename ${file1%-*})-${current_date}.xlsx"
else
cp -n "${file1}" "${to_dir}/$( basename ${file1%-*})-${current_date}.xlsx"
fi
}
tscp "$#"
It's usage is as follows:
tscp source to_directory [-—force]
Basically the script takes 2 arguments and the 3rd one is optional.
First arg is source file path and second are is the directory path to where you want to copy (. if same directory).
By default this copy would be made if and only if destination file doesn't exist.
If you want to overwrite the destination file then pass a third arg —force.
Again, this can be refined much much more based on details provided.
Sample usage for now:
bash tscp SUBSCRIBED_STUDENTS_20200217074343-20200217.xlsx /incoming/F1/
will copy SUBSCRIBED_STUDENTS_20200217074343-20200217.xlsx to directory /incoming/F1/ with updated date if it doesn't exist yet.
UPDATE:
Give this a go:
#! /usr/bin/env bash
printf_err() {
ERR_COLOR='\033[0;31m'
NORMAL_COLOR='\033[0m'
printf "${ERR_COLOR}$1${NORMAL_COLOR}" ; shift
printf "${ERR_COLOR}%s${NORMAL_COLOR}\n" "$#" >&2
}
alias printf_err='printf_err "Line ${LINENO}: " '
shopt -s expand_aliases
usage() {
printf_err \
"" \
"usage: ${BASH_SOURCE##*/} " \
" -f copy_data_file" \
" -d days_before" \
" -m months_before" \
" -o" \
" -y years_before" \
" -r " \
" -t to_dir" \
>&2
exit 1
}
fullpath() {
local path="$1" ; shift
local abs_path
if [ -z "${path}" ] ; then
printf_err "${BASH_SOURCE}: Line ${LINENO}: param1(path) is empty"
return 1
fi
abs_path="$( cd "$( dirname "${path}" )" ; pwd )/$( basename ${path} )"
printf "${abs_path}"
}
OVERWRITE=0
REVIEW=0
COPYSCRIPT="$( mktemp "/tmp/copyscriptXXXXX" )"
while getopts 'f:d:m:y:t:or' option
do
case "${option}" in
d)
DAYS="${OPTARG}"
;;
f)
INPUT_FILE="${OPTARG}"
;;
m)
MONTHS="${OPTARG}"
;;
t)
TO_DIR="${OPTARG}"
;;
y)
YEARS="${OPTARG}"
;;
o)
OVERWRITE=1
;;
r)
REVIEW=1
COPYSCRIPT="copyscript"
;;
*)
usage
;;
esac
done
INPUT_FILE=${INPUT_FILE:-$1}
TO_DIR=${TO_DIR:-$2}
if [ ! -f "${INPUT_FILE}" ] ; then
printf_err "No such file ${INPUT_FILE}"
usage
fi
DAYS="${DAYS:-1}"
MONTHS="${MONTHS:-0}"
YEARS="${YEARS:-0}"
if date -v -1d > /dev/null 2>&1; then
# BSD date
previous_date="$( date -v -${DAYS}d -v -${MONTHS}m -v -${YEARS}y '+%Y%m%d' )"
else
# GNU date
previous_date="$( date --date="-${DAYS} days -${MONTHS} months -${YEARS} years" '+%Y%m%d' )"
fi
current_date="$( date '+%Y%m%d' )"
tmpfile="$( mktemp "/tmp/dstnamesXXXXX" )"
awk -v to_replace="${previous_date}" -v replaced="${current_date}" '{
gsub(to_replace, replaced, $0)
print
}' ${INPUT_FILE} > "${tmpfile}"
paste ${INPUT_FILE} "${tmpfile}" |
while IFS=$'\t' read -r -a arr
do
src=${arr[0]}
dst=${arr[1]}
opt=${arr[2]}
if [ -n "${opt}" ] ; then
if [ ! -d "${dst}" ] ;
then
printf_err "No such directory ${dst}"
usage
fi
dst="${dst}/$( basename "${opt}" )"
else
if [ ! -d "${TO_DIR}" ] ;
then
printf_err "No such directory ${TO_DIR}"
usage
fi
dst="${TO_DIR}/$( basename "${dst}" )"
fi
src=$( fullpath "${src}" )
dst=$( fullpath "${dst}" )
if [ -n "${OVERWRITE}" ] ; then
echo "cp ${src} ${dst}"
else
echo "cp -n ${src} ${dst}"
fi
done > "${COPYSCRIPT}"
if [ "${REVIEW}" -eq 0 ] ; then
${BASH} "${COPYSCRIPT}"
rm "${COPYSCRIPT}"
fi
rm "${tmpfile}"
Steps:
Store the above script in a file, say `tscp`.
Now you need to create the input file for it.
From you example, a sample input file can be like:
STUDENT_ACCOUNTS_20200217074343-20200217.xlsx /incoming/A1/
STUDENT_MARKS_20200217074343-20200217.xlsx /incoming/B1/
STUNDENT_HOMEWORKS_20200217074343-20200217.xlsx
STUDENT_PHYSICAL_20200217074343-20200217.xlsx
SUBSCRIBED_STUDENTS_20200217074343-20200217.xlsx /incoming/FI/
Where first part is the source file name and after a "tab" (it should be a tab for sure), you mention the destination directory. These paths should be either absolute or relative the the directory where you are executing the script. You may not mention destination directory if all are to be sent to same directory (discussed later).
Let's say you named this file `file`.
Also, you don't really have to type all that. If you have these files in the current directory, just do this:
ls -1 > file
(the above is ls "one", not "l".)
Now we have the `file` from above in which we didn't mention destination directory for all but only for some.
Let's say we want to move all other directories to `/incoming/x` and it exists.
Now script is to be executed like:
bash tscp -f file -t /incoming/x -r
Where `/incoming/x` is the default directory i.e. when none other directory is mentioned in `file`, your files are moved to this directory.
Now in the current directory a script named `copyscript` will be generated which will contain `cp` commands to copy all files. You can open a review `copyscript` and if the copying seems right, go ahead and:
bash copyscript
which will copy all the files and then you can:
rm copyscript
You need not generate to `copyscript` and can straight away go for a copy like:
bash tscp -f file -t /incoming/x
which won't generate any copyscript and copy straight away.
Previously `-r` caused the generation of `copyscript`.
I would recomment to use version with `-r` because that is a little safer and you will be sure that right copies are being made.
By default it would check for the previous day and rename to current date, but you can override that behaviour as:
bash tscp -f file -t /incoming/x -d 3
`-d 3` would look for 3 days back files in `file`.
By default copies won't overwrite i.e. if file at the destination already exists, copies won't be made.
If you want to overwrite, add flag `-o`.
As a conclusion I would advice to use:
bash tscp -f file -r
where file contains tab separated values like above for all.
Also, adding tscp to path would be a good idea after you are sure it works ok.
Also the scipt is made on mac and there is always a change of version clash of tools used. I would suggest to try the script on some sample data first to make sure script works right on your machine.

Copy Folders Recursively: Shell

My code takes two arguments from the user. My goal is to find the folder given by the user (the first argument) and make as many copies as they want of it (the second argument). As of right now, my code recursively prints out all subdirectories and files within the subdirectories... My code also copies files as many times as the user specifies. However, that's my problem, my copy function only works on files and not folders... I am wondering how to modify my copy function (or any other part of the code) so that it recursively copies the specified folder along with all of its original content
I know my cp function towards the bottom of the code needs to be changed to
-r ./sourceFolder ./destFolder but I do not know how to do that given the arguments passed in. After all, the destination folder name will just be the original folder with an incrementing number at the end of it.
#!/bin/bash
read -p "Your folder name is $1 and the number of copies is $2. Press Y for yes N for no " -n 1 -r
if ! [[ $REPLY =~ ^[Yy]$ ]]
then
echo
echo "Rerun script and pass in the folder and how many copies yo would like (e.g folder 4)"
exit
fi
echo
echo "-------------COPY FILE----------------"
FOLDER=$1
for f IN $folder
do
if [ ! -f "$FOLDER" ]
then
echo "folder "$FOLDER" does not exist"
exit 1
fi
done
DIR="."
function list_files()
{
cd $1
echo; echo "$(pwd)":; #Display Directory name
for i in *
do
if test -d "$i" #if dictionary
then
list_files "$i" #recursively list files
cd ..
else
echo "$i"; #Display File name
fi
done
}
j=$2
for i in "$*"
do
DIR=$1
list_files "$DIR"
for ((i=1; i<J; i++))
do
cp "$1" "$1$i"; #copies the file i amount of times, and creates new files with names that increment by 1
done
shift 1
done
If you want to copy recursive you can use cp -r <source folder> <destination folder>.
This will copy the content of the source file to the destination folder.
#!/bin/bash
read -p "Your folder name is $1 and the number of copies is $2. Press Y for yes N for no " -n 1 -r
if ! [[ $REPLY =~ ^[Yy]$ ]]
then
echo
echo "Rerun script and pass in the folder and how many copies yo would like (e.g folder 4)"
exit
fi
echo
echo "-------------COPY FILE----------------"
FOLDER=$1
if [ ! -d "$FOLDER" ]
then
echo "folder $FOLDER does not exist"
exit 1
fi
j=$2
for ((i=1; i<=j; i++))
do
cp -r "$1" "$1$i"; #copies the file i amount of times, and creates new files with names that increment by 1
echo "folder $1 copied to $1$i"
done
I changed the folder check from -f to -d, changed the variable nameing a bit (case), removed the list_files function and changed in the last for loop the i<$j to i<=j because the loop starts with 1. Then I added the -r and it works.

Nested for loop to enter and exit multiple directories Bash script

As an example, I have 7 directories each containing 4 files. The 4 files follow the following naming convention name_S#_L001_R1_001.fastq.gz. The sed command is to partially keep the unique file name.
I have a nested for loop in order to enter a directory and perform a command, exit the directory and proceed to the next directory. Everything seems to be working beautifully, however the code gets stuck on the last directory looping 4 times.
for f in /completepath/*
do
[ -d $f ] && cd "$f" && echo Entering into $f
for y in `ls *.fastq.gz | sed 's/_L00[1234]_R1_001.fastq.gz//g' | sort -u`
do
echo ${y}
done
done
Example output-
Entering into /completepath/m_i_cast_avpv_1
iavpvcast1_S6
Entering into /completepath/m_i_cast_avpv_2
iavpvcast2_S6
Entering into /completepath/m_i_int_avpv_1
iavpvint1_S5
Entering into /completepath/m_i_int_avpv_2
iavpvint2_S5
Entering into /completepath/m_p_cast_avpv_1
pavpvcast1_S8
Entering into /completepathd/m_p_int_avpv_1
pavpvint1_S7
Entering into /completepath/m_p_int_avpv_2
pavpvint2_S7
pavpvint2_S7
pavpvint2_S7
pavpvint2_S7
Any recommendations of how to correctly exit the inner loop?
It looks like /completepath/ contains some entries that are not directories. When the loop over /completepath/* sees something that's not a directory, it doesn't enter it, thanks to the [ -d $f ] check.
But it still continues to run the next for y in ... loop.
At that point the script is still in the previous directory it has seen.
One way to solve that is to skip the rest of the loop when $f is not a directory:
if [ -d $f ]; then
cd "$f" && echo Entering into $f
else
continue
fi
There's an even better way. By writing /completepath/*/ only directory entries will be matched, so you can simplify your loop to this:
for f in /completepath/*/
do
cd "$f" && echo "Entering into $f" || { echo "Error: could not enter into $f"; continue; }
for y in $(ls *.fastq.gz | sed 's/_L00[1234]_R1_001.fastq.gz//g' | sort -u)
do
echo ${y}
done
done

Shell script to poll a directory and stop upon an event

Need shell script to:
1/keep polling a directory "receive_dir" irrespective of having files or no files in it.
2/move the files over to another directory "send_dir".
3/the script should only stop polling upon a file "stopfile" get moved to "receive_dir". Thanks !!
My script:
until [ $i = stopfile ]
do
for i in `ls receive_dir`; do
time=$(date +%m-%d-%Y-%H:%M:%S)
echo $time
mv receive_dir/$i send_dir/;
done
done
This fails on empty directories and also is there any better way ?
If you are running on Linux, you might wish to consider inotifywait
$ declare -f tillStopfile
tillStopfile ()
{
cd receive_dir
[[ -d ../send_dir ]] || mkdir ../send_dir
while true; do
date +%m-%d-%Y-%H:%M:%S
for f in *
do
mv "$f" ../send_dir
[[ $f == "stopfile" ]] && break 2
done
sleep 3
done
}
$
Improvements
while true ... break #
easier to control this loop
cd receive_dir #
why not run in the "receive_dir"
factor date out of inner loop #
unless you need to see each time-stamp?
added suggested "sleep"
# pick a suitable inteval
Run:
$ tillStopfile 2>/dev/null # suppresses ls error messages

How do I check if a directory exists or not in a Bash shell script?

What command checks if a directory exists or not within a Bash shell script?
To check if a directory exists:
if [ -d "$DIRECTORY" ]; then
echo "$DIRECTORY does exist."
fi
To check if a directory does not exist:
if [ ! -d "$DIRECTORY" ]; then
echo "$DIRECTORY does not exist."
fi
However, as Jon Ericson points out, subsequent commands may not work as intended if you do not take into account that a symbolic link to a directory will also pass this check.
E.g. running this:
ln -s "$ACTUAL_DIR" "$SYMLINK"
if [ -d "$SYMLINK" ]; then
rmdir "$SYMLINK"
fi
Will produce the error message:
rmdir: failed to remove `symlink': Not a directory
So symbolic links may have to be treated differently, if subsequent commands expect directories:
if [ -d "$LINK_OR_DIR" ]; then
if [ -L "$LINK_OR_DIR" ]; then
# It is a symlink!
# Symbolic link specific commands go here.
rm "$LINK_OR_DIR"
else
# It's a directory!
# Directory command goes here.
rmdir "$LINK_OR_DIR"
fi
fi
Take particular note of the double-quotes used to wrap the variables. The reason for this is explained by 8jean in another answer.
If the variables contain spaces or other unusual characters it will probably cause the script to fail.
Always wrap variables in double quotes when referencing them in a Bash script.
if [ -d "$DIRECTORY" ]; then
# Will enter here if $DIRECTORY exists, even if it contains spaces
fi
Kids these days put spaces and lots of other funny characters in their directory names. (Spaces! Back in my day, we didn't have no fancy spaces!)
One day, one of those kids will run your script with $DIRECTORY set to "My M0viez" and your script will blow up. You don't want that. So use double quotes.
Note the -d test can produce some surprising results:
$ ln -s tmp/ t
$ if [ -d t ]; then rmdir t; fi
rmdir: directory "t": Path component not a directory
File under: "When is a directory not a directory?" The answer: "When it's a symlink to a directory." A slightly more thorough test:
if [ -d t ]; then
if [ -L t ]; then
rm t
else
rmdir t
fi
fi
You can find more information in the Bash manual on Bash conditional expressions and the [ builtin command and the [[ compound commmand.
I find the double-bracket version of test makes writing logic tests more natural:
if [[ -d "${DIRECTORY}" && ! -L "${DIRECTORY}" ]] ; then
echo "It's a bona-fide directory"
fi
Shorter form:
# if $DIR is a directory, then print yes
[ -d "$DIR" ] && echo "Yes"
A simple script to test if a directory or file is present or not:
if [ -d /home/ram/dir ] # For file "if [ -f /home/rama/file ]"
then
echo "dir present"
else
echo "dir not present"
fi
A simple script to check whether the directory is present or not:
mkdir tempdir # If you want to check file use touch instead of mkdir
ret=$?
if [ "$ret" == "0" ]
then
echo "dir present"
else
echo "dir not present"
fi
The above scripts will check if the directory is present or not
$? if the last command is a success it returns "0", else a non-zero value.
Suppose tempdir is already present. Then mkdir tempdir will give an error like below:
mkdir: cannot create directory ‘tempdir’: File exists
To check if a directory exists you can use a simple if structure like this:
if [ -d directory/path to a directory ] ; then
# Things to do
else #if needed #also: elif [new condition]
# Things to do
fi
You can also do it in the negative:
if [ ! -d directory/path to a directory ] ; then
# Things to do when not an existing directory
Note: Be careful. Leave empty spaces on either side of both opening and closing braces.
With the same syntax you can use:
-e: any kind of archive
-f: file
-h: symbolic link
-r: readable file
-w: writable file
-x: executable file
-s: file size greater than zero
You can use test -d (see man test).
-d file True if file exists and is a directory.
For example:
test -d "/etc" && echo Exists || echo Does not exist
Note: The test command is same as conditional expression [ (see: man [), so it's portable across shell scripts.
[ - This is a synonym for the test builtin, but the last argument must, be a literal ], to match the opening [.
For possible options or further help, check:
help [
help test
man test or man [
Or for something completely useless:
[ -d . ] || echo "No"
Here's a very pragmatic idiom:
(cd $dir) || return # Is this a directory,
# and do we have access?
I typically wrap it in a function:
can_use_as_dir() {
(cd ${1:?pathname expected}) || return
}
Or:
assert_dir_access() {
(cd ${1:?pathname expected}) || exit
}
The nice thing about this approach is that I do not have to think of a good error message.
cd will give me a standard one line message to standard error already. It will also give more information than I will be able to provide. By performing the cd inside a subshell ( ... ), the command does not affect the current directory of the caller. If the directory exists, this subshell and the function are just a no-op.
Next is the argument that we pass to cd: ${1:?pathname expected}. This is a more elaborate form of parameter substitution which is explained in more detail below.
Tl;dr: If the string passed into this function is empty, we again exit from the subshell ( ... ) and return from the function with the given error message.
Quoting from the ksh93 man page:
${parameter:?word}
If parameter is set and is non-null then substitute its value;
otherwise, print word and exit from the shell (if not interactive).
If word is omitted then a standard message is printed.
and
If the colon : is omitted from the above expressions, then the
shell only checks whether parameter is set or not.
The phrasing here is peculiar to the shell documentation, as word may refer to any reasonable string, including whitespace.
In this particular case, I know that the standard error message 1: parameter not set is not sufficient, so I zoom in on the type of value that we expect here - the pathname of a directory.
A philosophical note:
The shell is not an object oriented language, so the message says pathname, not directory. At this level, I'd rather keep it simple - the arguments to a function are just strings.
if [ -d "$Directory" -a -w "$Directory" ]
then
#Statements
fi
The above code checks if the directory exists and if it is writable.
More features using find
Check existence of the folder within sub-directories:
found=`find -type d -name "myDirectory"`
if [ -n "$found" ]
then
# The variable 'found' contains the full path where "myDirectory" is.
# It may contain several lines if there are several folders named "myDirectory".
fi
Check existence of one or several folders based on a pattern within the current directory:
found=`find -maxdepth 1 -type d -name "my*"`
if [ -n "$found" ]
then
# The variable 'found' contains the full path where folders "my*" have been found.
fi
Both combinations. In the following example, it checks the existence of the folder in the current directory:
found=`find -maxdepth 1 -type d -name "myDirectory"`
if [ -n "$found" ]
then
# The variable 'found' is not empty => "myDirectory"` exists.
fi
DIRECTORY=/tmp
if [ -d "$DIRECTORY" ]; then
echo "Exists"
fi
Try online
Actually, you should use several tools to get a bulletproof approach:
DIR_PATH=`readlink -f "${the_stuff_you_test}"` # Get rid of symlinks and get abs path
if [[ -d "${DIR_PATH}" ]] ; Then # Now you're testing
echo "It's a dir";
fi
There isn't any need to worry about spaces and special characters as long as you use "${}".
Note that [[]] is not as portable as [], but since most people work with modern versions of Bash (since after all, most people don't even work with command line :-p), the benefit is greater than the trouble.
Have you considered just doing whatever you want to do in the if rather than looking before you leap?
I.e., if you want to check for the existence of a directory before you enter it, try just doing this:
if pushd /path/you/want/to/enter; then
# Commands you want to run in this directory
popd
fi
If the path you give to pushd exists, you'll enter it and it'll exit with 0, which means the then portion of the statement will execute. If it doesn't exist, nothing will happen (other than some output saying the directory doesn't exist, which is probably a helpful side-effect anyways for debugging).
It seems better than this, which requires repeating yourself:
if [ -d /path/you/want/to/enter ]; then
pushd /path/you/want/to/enter
# Commands you want to run in this directory
popd
fi
The same thing works with cd, mv, rm, etc... if you try them on files that don't exist, they'll exit with an error and print a message saying it doesn't exist, and your then block will be skipped. If you try them on files that do exist, the command will execute and exit with a status of 0, allowing your then block to execute.
[[ -d "$DIR" && ! -L "$DIR" ]] && echo "It's a directory and not a symbolic link"
N.B: Quoting variables is a good practice.
Explanation:
-d: check if it's a directory
-L: check if it's a symbolic link
To check more than one directory use this code:
if [ -d "$DIRECTORY1" ] && [ -d "$DIRECTORY2" ] then
# Things to do
fi
Check if the directory exists, else make one:
[ -d "$DIRECTORY" ] || mkdir $DIRECTORY
[ -d ~/Desktop/TEMPORAL/ ] && echo "DIRECTORY EXISTS" || echo "DIRECTORY DOES NOT EXIST"
Using the -e check will check for files and this includes directories.
if [ -e ${FILE_PATH_AND_NAME} ]
then
echo "The file or directory exists."
fi
This answer wrapped up as a shell script
Examples
$ is_dir ~
YES
$ is_dir /tmp
YES
$ is_dir ~/bin
YES
$ mkdir '/tmp/test me'
$ is_dir '/tmp/test me'
YES
$ is_dir /asdf/asdf
NO
# Example of calling it in another script
DIR=~/mydata
if [ $(is_dir $DIR) == "NO" ]
then
echo "Folder doesnt exist: $DIR";
exit;
fi
is_dir
function show_help()
{
IT=$(CAT <<EOF
usage: DIR
output: YES or NO, depending on whether or not the directory exists.
)
echo "$IT"
exit
}
if [ "$1" == "help" ]
then
show_help
fi
if [ -z "$1" ]
then
show_help
fi
DIR=$1
if [ -d $DIR ]; then
echo "YES";
exit;
fi
echo "NO";
As per Jonathan's comment:
If you want to create the directory and it does not exist yet, then the simplest technique is to use mkdir -p which creates the directory — and any missing directories up the path — and does not fail if the directory already exists, so you can do it all at once with:
mkdir -p /some/directory/you/want/to/exist || exit 1
if [ -d "$DIRECTORY" ]; then
# Will enter here if $DIRECTORY exists
fi
This is not completely true...
If you want to go to that directory, you also need to have the execute rights on the directory. Maybe you need to have write rights as well.
Therefore:
if [ -d "$DIRECTORY" ] && [ -x "$DIRECTORY" ] ; then
# ... to go to that directory (even if DIRECTORY is a link)
cd $DIRECTORY
pwd
fi
if [ -d "$DIRECTORY" ] && [ -w "$DIRECTORY" ] ; then
# ... to go to that directory and write something there (even if DIRECTORY is a link)
cd $DIRECTORY
touch foobar
fi
In kind of a ternary form,
[ -d "$directory" ] && echo "exist" || echo "not exist"
And with test:
test -d "$directory" && echo "exist" || echo "not exist"
file="foo"
if [[ -e "$file" ]]; then echo "File Exists"; fi;
The ls command in conjunction with -l (long listing) option returns attributes information about files and directories.
In particular the first character of ls -l output it is usually a d or a - (dash). In case of a d the one listed is a directory for sure.
The following command in just one line will tell you if the given ISDIR variable contains a path to a directory or not:
[[ $(ls -ld "$ISDIR" | cut -c1) == 'd' ]] &&
echo "YES, $ISDIR is a directory." ||
echo "Sorry, $ISDIR is not a directory"
Practical usage:
[claudio#nowhere ~]$ ISDIR="$HOME/Music"
[claudio#nowhere ~]$ ls -ld "$ISDIR"
drwxr-xr-x. 2 claudio claudio 4096 Aug 23 00:02 /home/claudio/Music
[claudio#nowhere ~]$ [[ $(ls -ld "$ISDIR" | cut -c1) == 'd' ]] &&
echo "YES, $ISDIR is a directory." ||
echo "Sorry, $ISDIR is not a directory"
YES, /home/claudio/Music is a directory.
[claudio#nowhere ~]$ touch "empty file.txt"
[claudio#nowhere ~]$ ISDIR="$HOME/empty file.txt"
[claudio#nowhere ~]$ [[ $(ls -ld "$ISDIR" | cut -c1) == 'd' ]] &&
echo "YES, $ISDIR is a directory." ||
echo "Sorry, $ISDIR is not a directoy"
Sorry, /home/claudio/empty file.txt is not a directory
There are great solutions out there, but ultimately every script will fail if you're not in the right directory. So code like this:
if [ -d "$LINK_OR_DIR" ]; then
if [ -L "$LINK_OR_DIR" ]; then
# It is a symlink!
# Symbolic link specific commands go here
rm "$LINK_OR_DIR"
else
# It's a directory!
# Directory command goes here
rmdir "$LINK_OR_DIR"
fi
fi
will execute successfully only if at the moment of execution you're in a directory that has a subdirectory that you happen to check for.
I understand the initial question like this: to verify if a directory exists irrespective of the user's position in the file system. So using the command 'find' might do the trick:
dir=" "
echo "Input directory name to search for:"
read dir
find $HOME -name $dir -type d
This solution is good because it allows the use of wildcards, a useful feature when searching for files/directories. The only problem is that, if the searched directory doesn't exist, the 'find' command will print nothing to standard output (not an elegant solution for my taste) and will have nonetheless a zero exit. Maybe someone could improve on this.
The below find can be used,
find . -type d -name dirname -prune -print
One Liner:
[[ -d $Directory ]] && echo true
(1)
[ -d Piyush_Drv1 ] && echo ""Exists"" || echo "Not Exists"
(2)
[ `find . -type d -name Piyush_Drv1 -print | wc -l` -eq 1 ] && echo Exists || echo "Not Exists"
(3)
[[ -d run_dir && ! -L run_dir ]] && echo Exists || echo "Not Exists"
If an issue is found with one of the approaches provided above:
With the ls command; the cases when a directory does not exists - an error message is shown
[[ `ls -ld SAMPLE_DIR| grep ^d | wc -l` -eq 1 ]] && echo exists || not exists
-ksh: not: not found [No such file or directory]

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