i have the following bash script on my server:
today=$(date +"%Y-%m-%d")
find /backups/www -type f -mtime -1|xargs tar uf /daily/backup-$today.tar
as you can see it creates backups of files modified/created in the last 24h. However if no files are found, it creates corrupted tar file. I would like to wrap it in if..fi statement so id doesn't create empty/corrupted tar files.
Can someone help me modify this script?
Thanks
You can check if result is ok then check if result is empty :
today=$(date +"%Y-%m-%d")
results=`find /backups/www -type f -mtime -1`
if [[ 0 == $? ]] ; then
if [[ -z $results ]] ; then
echo "No files found"
else
tar uf /daily/backup-$today.tar $results
fi
else
echo "Search failed"
fi
find /backups/www -type f -mtime -1 -exec tar uf /daily/backup-$today.tar {} +
Using -exec is preferable to xargs. There's no pipeline needed and it will handle file names with spaces, newlines, and other unusual characters without extra work. The {} at the end is a placeholder for the file names, and + marks the end of the -exec command (in case there were more arguments to find).
As a bonus it won't execute the command if no files are found.
One relatively simple trick would be this:
today=$(date +"%Y-%m-%d")
touch /backups/www/.timestamp
find /backups/www -type f -mtime -1|xargs tar uf /daily/backup-$today.tar
That way you're guaranteed to always find at least one file (and it's minimal in size).
xargs -r does nothing if there is no input.
Related
I have the following 2 scripts, that recursively convert folders of images to pdf's for my wifes japanese manga kindle using find and Imagemagick convert:
#!/bin/bash
_d="$(pwd)"
echo "$_d"
find . -type d -exec echo "Will convert in the following order: {}" \;
find . -type d -exec echo "Converting: '{}'" \; -exec convert '{}/*.jpg' "$_d/{}.pdf" \;
and the same for PNG
#!/bin/bash
_d="$(pwd)"
echo "$_d"
find . -type d -exec echo "Will convert in the following order: {}" \;
find . -type d -exec echo "Converting: '{}'" \; -exec convert '{}/*.png' "$_d/{}.pdf" \;
Unfortunately I am not able make one universal script that works for all image formats.
How do I make one script that works for both ?
I would also need JPG,PNG as well as jpeg,JPEG
Thx in advance
I wouldn't use find at all, just a loop:
#!/use/bin/env bash
# enable recursive globs
shopt -s globstar
for dir in **/*/; do
printf "Converting jpgs in %s\n" "$dir"
convert "$dir"/*.jpg "$dir/out.pdf"
done
If you want to combine .jpg and .JPG in the same pdf, add nocaseglob to the shopt line. Add .jpeg to the mix? Add extglob and change "$dir"/*.jpg to "$dir"/*.#(jpg|jpeg)
You can do more complicated actions if you turn the find exec into a bash function (or even a standalone script).
#!/bin/bash
do_convert()(
shopt -s nullglob
for dir in "$#"; do
files=("$dir"/*.{jpg,JPG,PNG,jpeg,JPEG})
if [[ -z $files ]]; then
echo 1>&2 "no suitable files in $dir"
continue
fi
echo "Converting $dir"
convert "${files[#]}" "$dir.pdf"
done
)
export -f do_convert
pwd
echo "Will convert in the following order:"
find . -type d
# find . -type d -exec bash -c 'do_convert {}' \;
find . -type d -exec bash -c 'do_convert "$#"' -- {} \+
nullglob makes *.xyz return nothing if there is no match, instead of returning the original string unchanged
p/*.{a,b,c} expands into p/*.a p/*.b p/*.c before the * are expanded
x()(...) instead of the more normal x(){...} uses a subshell so we don't have to remember to unset nullglob again or clean up any variable definitions
export -f x makes function x available in subshells
we skip conversion if there are no suitable files
with the slightly more complicated find command, we can reduce the number of invocations of bash (probably doesn't save a great deal in this particular case)
how about a one-liner
dry-run
find -name \*.jpg -or -name \*.png | xargs -I xxx echo "xxx =>" xxx.pdf
run
find -name \*.jpg -or -name \*.png | xargs -I xxx echo xxx xxx.pdf
help
-name match name
-or logical or => both jpg and png
xargs map input into a name to execute a command on
-I select a name, it is like {} in file
NOTE
instead of $(pwd) which is a command substitution you can use variable $PWD
xxx maps into a name and xxx.pdf still has the matched extension found by find. which means filename.png becomes filename.png.pdf. If this is not desired, you can sed it
to run convert command in parallel you can use -P 0 with xargs -- see xargs --help
With sed to remove extensions
dry-run
find -name \*.jpg -or -name \*.png | sed 's/.\(png\|jpg\)$//g' | xargs -I xxx echo "xxx =>" xxx.pdf
#shawn Your solution works, just as I stated in the comments, I am to stupid to name the resulting pdf properly (folder name) and save in the script caller directory. Nevertheless, it solves my case insensitive jpg, jpeg, png problems just fine.
Here is shawns solution:
#!/bin/bash
# enable recursive globs
shopt -s globstar nocaseglob extglob
for dir in **/*/; do
printf "Converting (jpg|jpeg|png) in %s\n" "$dir"
convert "$dir"/*.#(jpg|jpeg|png) "$dir/out.pdf"
done
#jhnc Your solution works out of the box, it does exactly what I intended, and I really like calling functions, or even standalone scripts to increase complexity. One drawback is, that I can not Ctrl-c the process, because it is thereby threaded, or runs in a subshell ? I think you were missing an exit statement at the end of the function, it never stopped.
#!/bin/bash
do_convert()(
shopt -s nullglob
for dir in "$#"; do
files=("$dir"/*.{jpg,JPG,png,PNG,jpeg,JPEG})
if [[ -z $files ]]; then
echo 1>&2 "no suitable files in $dir"
continue
fi
echo "Converting $dir"
convert "${files[#]}" "$dir.pdf"
done
exit
)
export -f do_convert
pwd
echo "Will convert in the following order:"
find . -type d
# find . -type d -exec bash -c 'do_convert {}' \;
find . -type d -exec bash -c 'do_convert "$#"' -- {} \+
# everyone else, it's already after midnight again, I guess this is a trivial question for you guys, and I am very grateful for your ALL your answers, I didn't have the time to try everything.
I find linux bash very challenging.
A lot of ways to skin this cat. My thought is:
for F in `find . -type f -print`
do
TYPE=`file -n --mime-type $F`
if [ "$TYPE" = image/png ]
then
## do png conversion here
elif [ "$TYPE" = image/jpg ]
then
## do jpg conversion here
fi
done
I have series of directories with (mostly) video files in them, say
test1
1.mpg
2.avi
3.mpeg
junk.sh
test2
123.avi
432.avi
432.srt
test3
asdf.mpg
qwerty.mpeg
I create a variable (video_dir) with the directory names (based on other parameters) and use that with find to generate the basic list. I then filter based on another variable (video_type) for file types (because there is sometimes non-video files in the dirs) piping it through egrep. Then I shuffle the list around and save it out to a file. That file is later used by mplayer to slideshow through the list.
I currently use the following command to accomplish that. I'm sure it's a horrible way to do it, but it works for me and it's quite fast even on big directories.
video_dir="/test1 /test2"
video_types=".mpg$|.avi$|.mpeg$"
find ${video_dir} -type f |
egrep -i "${video_types}" |
shuf > "$TEMP_OUT"
I now would like to add the ability to filter out files based on the resolution height of the video file. I can get that from.
mediainfo --Output='Video;%Height%' filename
Which just returns a number. I have tried using the -exec functionality of find to run that command on each file.
find ${video_dir} -type f -exec mediainfo --Output='Video;%Height%' {} \;
but that just returns the list of heights, not the filenames and I can't figure out how to reject ones based on a comparison, like <480.
I could do a for next loop but that seems like a bad (slow) idea.
Using info from #mark-setchell I modified it to,
video_dir="test1"
find ${video_dir} -type f \
-exec bash -c 'h=$(mediainfo --Output="Video;%Height%" "$1"); [[ $h -gt 480 ]]' _ {} \; -print
Which works.
You can replace your egrep with the following so you are still inside the find command (-iname is case insensitive and -o represents a logical OR):
find test1 test2 -type f \
\( -iname "*.mpg" -o -iname "*.avi" -o -iname "*.mpeg" \) \
NEXT_BIT
The NEXT_BIT can then -exec bash and exit with status 0 or 1 depending on whether you want the current file included or excluded. So it will look like this:
-exec bash -c 'H=$(mediainfo -output ... "$1"); [ $H -lt 480 ] && exit 1; exit 0' _ {} \;
So, taking note of #tripleee advice in comments about superfluous exit statements, I get this:
find test1 test2 -type f \
\( -iname "*.mpg" -o -iname "*.avi" -o -iname "*.mpeg" \) \
-exec bash -c 'h=$(mediainfo ...options... "$1"); [ $h -lt 480 ]' _ {} \; -print
This Q&A was focused on one particular case, so the accepted answer is not as general as it could be.
find
If the list of files comes from find, one can use its filtering facilities, e.g. -exec:
find ${video_dir} -type f \
-exec COMMAND \; \
-print
Here
COMMAND is not enclosed in quotes -- find reads everything after -exec and up to a \;
find will expand {} to the current file name (including path -- you might find -execdir helpful, which will cd to the file's directory and replace {} with the leaf file name)
The exit code of COMMAND is treated as follows:
0 -> true
non-0 -> false
Note that you can build more complex expressions (e.g. -not -exec ...), which will be evaluated "from left to right, according to the rules of precedence ... -and is assumed where the operator is omitted." (per man find)
xargs
If the list of files comes from elsewhere (and is available on stdin), you can use xargs as follows (from
If xargs is map, what is filter? )
ls | xargs -I{} bash -c "COMMAND '{}' && echo '{}'"
Here is my solution.
#!/bin/bash
shopt -s nullglob
video_dir=(/test1 /test2)
while IFS= read -rd '' file; do
if [[ $file = *.#(mpg|avi|mpeg|mp4) ]]; then
h=$(mediainfo --Output="Video;%Height%" "$file")
(( h >= 480 )) && echo "$file"
fi
done < <(find "${video_dir[#]}" -type f -print0)
This solution you can process everything inside the while read loop.
I am trying to create a small bash script that essentially looks through a directory that includes hundreds of sub directories. in SOME of these subdirectories include a textfile.txt and a htmlfile.html where the names textfile and htmlfile are variable.
I only really care about sub directories that have both the .txt and the .html, all other subdirecories can be ignored.
I then want to list all the .html files and .txt files that are in the same sub directory
this seems like a pretty simple issue to solve but I am at a loss. all I can really get working is a line of code that outputs sub directories that have either a .html file or .txt with no association with the actual sub directory they are in, and I am pretty new at bash scripting so I can't go any further
#!/bin/bash
files="$(find ~/file/ -type f -name '*.txt' -or -name '*.html')"
for file in $files
do
echo $file
done
The following find command looks checks every subdirectory and, if it has both html and txt files, it lists all of them:
find . -type d -exec env d={} bash -c 'ls "$d"/*.html &>/dev/null && ls "$d"/*.txt &>/dev/null && ls "$d/"*.{html,txt}' \;
Explanation:
find . -type d
This looks for all subdirectories of the current directory.
-exec env d={} bash -c '...' \;
This sets the environment variable d to the value of the found subdirectory and then executes the bash command that is contained within the single quotes (see below).
ls "$d"/*.html &>/dev/null && ls "$d"/*.txt &>/dev/null && ls "$d/"*.{html,txt}
This is the bash command that is executed. It consists of three statements and-ed together. The first checks to see if directory d has any html files. If so, the second statement runs and it checks to see if there are any txt files. If so, the last statement is executed and it lists all html and txt files in the directory d.
This command is safe for all file and directory names containing spaces, tabs, or other difficult characters.
You could do it by searching recursively with the globstar option:
shopt -s globstar
for file in **; do
if [[ -d $file ]]; then
for sub_file in "$file"/*; do
case "$sub_file" in
*.html)
html=1;;
*.txt)
txt=1;;
esac
done
[[ $html && $txt ]] && echo "$file"
html=""
txt=""
fi
done
You can make use of -o
#!/bin/bash
files=$(find ~/file/ -type f -name '*.txt' -o -name '*.html')
for file in $files
do
echo $file
done
#!/bin/bash
#A quick peek into a dir to see if there's at least one file that matches pattern
dir_has_file() { dir="$1"; pattern="$2";
[ -n "$(find "$dir" -maxdepth 1 -type f -name "$pattern" -print -quit)" ]
}
#Assumes there are no newline characters in the filenames, but will behave correctly with subdirectories that match *.html or *.txt
find "$1" -type d|\
while read d
do
dir_has_file "$d" '*.txt' &&
dir_has_file "$d" '*.html' &&
#Now print all the matching files
find "$d" -maxdepth 1 -type f -name '*.txt' -o -name '*.html'
done
This script takes the root directory to look into as the first argument ($1).
The test command is what you need to check for the existence of each file in each of the subdirs:
find . -type d -exec sh -c "if test -f {}/$file1 -a -f {}/$file2 ; then ls {}/*.{txt,html} ; fi" \;
where $file1 and $file2 are the two .txt and .html files you are looking for.
I want to prepend text to the name of every file of a certain type - in this case .txt files - located in the current directory or a sub-directory.
I have tried:
find -L . -type f -name "*.txt" -exec mv "{}" "PrependedTextHere{}" \;
The problem with this is dealing with the ./ part of the path that comes with the {} reference.
Any help or alternative approaches appreciated.
You can do something like this
find -L . -type f -name "*.txt" -exec bash -c 'echo "$0" "${0%/*}/PrependedTextHere${0##*/}"' {} \;
Where
bash -c '...' executes the command
$0 is the first argument passed in, in this case {} -- the full filename
${0%/*} removes everything including and after the last / in the filename
${0##*/} removes everything before and including the last / in the filename
Replace the echo with a mv once you're satisfied it's working.
Are you just trying to move the files to a new file name that has Prepend before it?
for F in *.txt; do mv "$F" Prepend"$F"; done
Or do you want it to handle subdirectories and prepend between the directory and file name:
dir1/PrependA.txt
dir2/PrependB.txt
Here's a quick shot at it. Let me know if it helps.
for file in $(find -L . -type f -name "*.txt")
do
parent=$(echo $file | sed "s=\(.*/\).*=\1=")
name=$(echo $file | sed "s=.*/\(.*\)=\1=")
mv "$file" "${parent}PrependedTextHere${name}"
done
This ought to work, as long file names does not have new line character(s). In such case make the find to use -print0 and IFS to have null.
#!/bin/sh
IFS='
'
for I in $(find -L . -name '*.txt' -print); do
echo mv "$I" "${I%/*}/prepend-${I##*/}"
done
p.s. Remove the echo to make the script effective, it's there to avoid accidental breakage for people who randomly copy paste stuff from here to their shell.
how can I print out the name of each file in a certain directory with a specific extension?
Here's what I have so far:
#!/bin/sh
DIR="~/Desktop"
SUFFIX="in"
for file in $DIR/*.$SUFFIX
do
if [ -f $file ]; then
echo $file
fi
done
Unfortunately it doesn't work.
What's wrong with it?
In your DIR="~/Desktop" the "~" not expanded, because it is in "".
remove the "". DIR=~/Desktop
You could use find with -type f
#!/bin/sh
DIR="~/Desktop"
SUFFIX="in"
find "$DIR" -maxdepth 1 -type f -name "*.${SUFFIX}" -exec somecommand {} \;
For your information: "file" in Unix systems is typically the name of a command.
Its purpose is to analyze the files given as argument and infer the format. Example:
$ file entries.jar
entries.jar: Zip archive data, at least v2.0 to extract
for file in `ls $DIR/*.$SUFFIX`
Note the ls and backticks