Create a nested file while redirecting output - linux

In linux/OSx/etc, how can we redirect output to file inside a dir, where even dir needs to be created by this redirection.
basically, how to make sure that below command creates "dir1" and then sends output to "file1" inside "dir1"
echo "abc" > dir1/file1

You cannot do it with one command, you have to use mkdir:
filename="dir1/file1"
mkdir -p "$(dirname "$filename")" && echo "abc" > "$filename"

You can it with this one liner -
if [ ! -d "dir1" ]; then mkdir "dir1"; fi && echo "abc" > dir1/file1

Related

check to see if filepath exists bash linux script [duplicate]

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]

move or copy a file if that file exists?

I am trying to run a command
mv /var/www/my_folder/reports.html /tmp/
it is running properly. But I want to put a condition like if that file exists then only run the command. Is there anything like that?
I can put a shell file instead.
for shell a tried below thing
if [ -e /var/www/my_folder/reports.html ]
then
mv /var/www/my_folder/reports.html /tmp/
fi
But I need a command. Can some one help me with this?
Moving the file /var/www/my_folder/reports.html only if it exists and regular file:
[ -f "/var/www/my_folder/reports.html" ] && mv "/var/www/my_folder/reports.html" /tmp/
-f - returns true value if file exists and regular file
if exist file and then move or echo messages through standard error output
test -e /var/www/my_folder/reports.html && mv /var/www/my_folder/reports.html /tmp/ || echo "not existing the file" >&2
You can do it simply in a shell script
#!/bin/bash
# Check for the file
ls /var/www/my_folder/ | grep reports.html > /dev/null
# check output of the previous command
if [ $? -eq 0 ]
then
# echo -e "Found file"
mv /var/www/my_folder/reports.html /tmp/
else
# echo -e "File is not in there"
fi
Hope it helps
Maybe your use case is "Create if not exist, then copy always".
then: touch myfile && cp myfile mydest/

Create .txt of all files in each subdirectory

I need to create a text file in each subdirectory of all files in the list.
For example, subdirectory1 would contain a list of all of its files as a .txt and subdirectory2 would also contain a list of all of subdirectory2 files as a .txt.
I have tried
#!/bin/bash
for X in "$directory" *
do
if [ -d "$X" ];
then
cd "$X"
files="$(ls)"
echo "$files" >> filesNames.txt
fi
done
However this did not generate anything. I absolutely need it as a shell script because it will be part of a pipeline script, but I cannot seem to get it to work.
Here is the adjusted script giving me the no such file or directory comment. I know that the folder exists and have used it in commands that are run before this command.
#!/bin/bash
#Retrieve the base directory path
baseDir=$(dirname "$ini")
#Retrieve the reference genome path
ref=$(dirname "$genome")
#Create required directory structure
tested="$baseDir/tested"
MarkDups1="$baseDir/MarkDups1"
#don't create if already exists
[[ -d "tested" ]] || mkdir "$tested"
[[ -d "MarkDups1" ]] || mkdir "$MarkDups1"
#create a text file with all sorted and indexed bam files paths
#!/bin/bash
for x in $MarkDups1/*/;
do
(cd "$x"; ls > filesNames.txt)
done
The sequence to iterate over should be "$directory"/*/.
for x in "$directory"/*/; do
(cd "$x"
files=(*)
printf '%s\n' "${files[#]}" > filesNames.txt
)
done

linux zip and exclude dir via bash/shell script

I am trying to write a bash/shell script to zip up a specific folder and ignore certain sub-dirs in that folder.
This is the folder I am trying to zip "sync_test5":
My bash script generates an ignore list (based on) and calls the zip function like this:
#!/bin/bash
SYNC_WEB_ROOT_BASE_DIR="/home/www-data/public_html"
SYNC_WEB_ROOT_BACKUP_DIR="sync_test5"
SYNC_WEB_ROOT_IGNORE_DIR="dir_to_ignore dir2_to_ignore"
ignorelist=""
if [ "$SYNC_WEB_ROOT_IGNORE_DIR" != "" ];
then
for ignoredir in $SYNC_WEB_ROOT_IGNORE_DIR
do
ignorelist="$ignorelist $SYNC_WEB_ROOT_BACKUP_DIR/$ignoredir/**\*"
done
fi
FILE="$SYNC_BACKUP_DIR/$DATETIMENOW.website.zip"
cd $SYNC_WEB_ROOT_BASE_DIR;
zip -r $FILE $SYNC_WEB_ROOT_BACKUP_DIR -x $ignorelist >/dev/null
echo "Done"
Now this script runs without error, however it is not ignoring/excluding the dirs I've specified.
So, I had the shell script output the command it tried to run, which was:
zip -r 12-08-2014_072810.website.zip sync_test5 -x sync_test5/dir_to_ignore/**\* sync_test5/dir2_to_ignore/**\*
Now If I run the above command directly in putty like this, it works:
So, why doesn't my shell script exclude working as intended? the command that is being executed is identical (in shell and putty directly).
Because backslash quotings in a variable after word splitting are not evaluated.
If you have a='123\4', echo $a would give
123\4
But if you do it directly like echo 123\4, you'd get
1234
Clearly the arguments you pass with the variable and without the variables are different.
You probably just meant to not quote your argument with backslash:
ignorelist="$ignorelist $SYNC_WEB_ROOT_BACKUP_DIR/$ignoredir/***"
Btw, what actual works is a non-evaluated glob pattern:
zip -r 12-08-2014_072810.website.zip sync_test5 -x 'sync_test5/dir_to_ignore/***' 'sync_test5/dir2_to_ignore/***'
You can verify this with
echo zip -r 12-08-2014_072810.website.zip sync_test5 -x sync_test5/dir_to_ignore/**\* sync_test5/dir2_to_ignore/**\*
And this is my suggestion:
#!/bin/bash
SYNC_WEB_ROOT_BASE_DIR="/home/www-data/public_html"
SYNC_WEB_ROOT_BACKUP_DIR="sync_test5"
SYNC_WEB_ROOT_IGNORE_DIR=("dir_to_ignore" "dir2_to_ignore")
IGNORE_LIST=()
if [[ -n $SYNC_WEB_ROOT_IGNORE_DIR ]]; then
for IGNORE_DIR in "${SYNC_WEB_ROOT_IGNORE_DIR[#]}"; do
IGNORE_LIST+=("$SYNC_WEB_ROOT_BACKUP_DIR/$IGNORE_DIR/***") ## "$SYNC_WEB_ROOT_BACKUP_DIR/$IGNORE_DIR/*" perhaps is enough?
done
fi
FILE="$SYNC_BACKUP_DIR/$DATETIMENOW.website.zip" ## Where is $SYNC_BACKUP_DIR set?
cd "$SYNC_WEB_ROOT_BASE_DIR";
zip -r "$FILE" "$SYNC_WEB_ROOT_BACKUP_DIR" -x "${IGNORE_LIST[#]}" >/dev/null
echo "Done"
This is what I ended up with:
#!/bin/bash
# This script zips a directory, excluding specified files, types and subdirectories.
# while zipping the directory it excludes hidden directories and certain file types
[[ "`/usr/bin/tty`" == "not a tty" ]] && . ~/.bash_profile
DIRECTORY=$(cd `dirname $0` && pwd)
if [[ -z $1 ]]; then
echo "Usage: managed_directory_compressor /your-directory/ zip-file-name"
else
DIRECTORY_TO_COMPRESS=${1%/}
ZIPPED_FILE="$2.zip"
COMPRESS_IGNORE_FILE=("\.git" "*.zip" "*.csv" "*.json" "gulpfile.js" "*.rb" "*.bak" "*.swp" "*.back" "*.merge" "*.txt" "*.sh" "bower_components" "node_modules")
COMPRESS_IGNORE_DIR=("bower_components" "node_modules")
IGNORE_LIST=("*/\.*" "\.* "\/\.*"")
if [[ -n $COMPRESS_IGNORE_FILE ]]; then
for IGNORE_FILES in "${COMPRESS_IGNORE_FILE[#]}"; do
IGNORE_LIST+=("$DIRECTORY_TO_COMPRESS/$IGNORE_FILES/*")
done
for IGNORE_DIR in "${COMPRESS_IGNORE_DIR[#]}"; do
IGNORE_LIST+=("$DIRECTORY_TO_COMPRESS/$IGNORE_DIR/")
done
fi
zip -r "$ZIPPED_FILE" "$DIRECTORY_TO_COMPRESS" -x "${IGNORE_LIST[#]}" # >/dev/null
# echo zip -r "$ZIPPED_FILE" "$DIRECTORY_TO_COMPRESS" -x "${IGNORE_LIST[#]}" # >/dev/null
echo $DIRECTORY_TO_COMPRESS "compressed as" $ZIPPED_FILE.
fi
After a few trial and error, I have managed to fix this problem by changing this line:
ignorelist="$ignorelist $SYNC_WEB_ROOT_BACKUP_DIR/$ignoredir/**\*"
to:
ignorelist="$ignorelist $SYNC_WEB_ROOT_BACKUP_DIR/$ignoredir/***"
Not sure why this worked, but it does :)

Shell Scripting: Print directory names and files with specifics

In my script, I am asking the user to input a directory and then list all the files in that specific directory. What I want to do with that is to make the display a little better in which I would be able to display a "/" if the item in the directory is another directory and if it is an executable file (not an executable directory), print with a **".
This is what I have:
echo “Directory: “
read thing
for var123 in $thing*
do
echo $var123
done
In a directory I have a few folders and a few scripts that have the execute permission. when I run the script I want to say
/folder1/subfolder1/
/folder1/subfolder2/
/folder1/file1*
/folder1/file2*
I am new to this and have no clue what I am doing. Any help will be greatly appreciated.
You might want to check and make sure the user inputs something that ends in a / first.
e.g.
[[ $thing =~ '/'$ ]] || thing="$thing/"
Also check if it exists
e.g.
[[ -d $thing ]] || exit 1
Then for checking if it's a directory use the -d test as above. To check if executable file use -x. So putting that all together, try:
#!/bin/bash
echo “Directory: “
read thing
[[ $thing =~ '/'$ ]] || thing="$thing/"
[[ -d $thing ]] || exit 1
for var123 in "$thing"*
do
if [[ -f $var123 && -x $var123 ]]; then
echo "$var123**"
elif [[ -d $var123 ]]; then
echo "$var123/"
else
echo "$var123"
fi
done
ls -F is your friend here - if you want to do it for the current directory:
ls -F
If you want to do it for all files & subfolders of the current directory:
find * -exec ls -Fd {} \;
... and for a given directory:
echo "Directory: "
read DIR
find $DIR/* -exec ls -Fd {} \;
Edit: ls -F will append a / to directories and a * to executables. If you want ** instead, just use sed to replace them:
find $DIR/* -exec ls -Fd {} \; | sed 's/\*$/&&/'
And this approach works in all shells, not just bash.

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