I'm not a pro in shell scripting, thats why I ask here :).
Let's say I got a folder. I need a script that monitors that folder for new files (no prefix name of files is given). When a new file gets copied into that folder, another script should start. Has the second script processed the file successfully the file should be deleted.
I hope you can give me some ideas on how to achieve such script :)
Thank you very much in advance.
Thomas
Try this:
watcher.sh:
#!/bin/bash
if [ -z $1 ];
then
echo "You need to specify a dir as argument."
echo "Usage:"
echo "$0 <dir>"
exit 1
fi
while true;
do
for a in $(ls -1 $1/* 2>/dev/null);
do
otherscript $a && rm $a #calls otherscript with the file a as argument and removes it if otherscript returned something non-zero
done
sleep 2s
done
Don't forget to make it executable
chmod +x ./watcher.sh
call it with:
./watcher.sh <dirname>
try inotify(http://man7.org/linux/man-pages/man7/inotify.7.html)
or you may need to install inotify-tools (http://www.ibm.com/developerworks/linux/library/l-ubuntu-inotify/) to use it by shell.
Related
I'm looking to check if a variable file is in another directory, and if it is, stop the script from running any farther. So far I have this:
#! /bin/bash
for file in /directory/of/variable/file/*.cp;
do
test -f /directory/to/be/checked/$file;
echo $?
done
I ran an echo of $file and see that it includes the full path, which would explain why my test doesn't see the file, but I am at a loss for how to move forward so that I can check.
Any help would be greatly appreciated!
Thanks
I think you want
#! /bin/bash
for file in /directory/of/variable/file/*.cp ; do
newFile="${file##*/}"
if test -f /directory/to/be/checked/"$newFile" ; then
echo "/directory/to/be/checked/$newFile already exists, updating ..."
else
echo "/directory/to/be/checked/$newFile not found, copying ..."
fi
cp -i "$file" /directory/to/be/checked/"$newFile"
done
Note that you can replace cp -i with mv -i and move the file, leaving no file left behind in /directory/of/variable/file/.
The -i option means interrogate (I think), meaning if the file is already there, it will ask you overwrite /directory/to/be/checked/"$newFile" (or similar) to which you must reply y. This will only happen if the file already exists in the new location.
IHTH
The command basename will give you just the file (or directory) without the rest of the path.
#! /bin/bash
for file in /directory/of/variable/file/*.cp;
do
test -f /directory/to/be/checked/$(basename $file);
echo $?
done
I am a beginner in shell script and have to code a script to simulate the functionality of mv command of linux without actually using the mv command in my script. Please help me I will be very thankful !
If you want to simulate the mv command you need to copy the file that you want to "move" to the destination folder then you have to delete the old one.
Here is a little script:
#!/bin/bash
from=$1
to=$2
echo "Copy from $1 to $2"
cp $1 $2
echo "Removing the old file $1"
rm $1
echo "Done."`
Hope that will help you.
I'm having trouble executing some files under a BASH script.
What I want is, when running the SCRIPT.SH, to check if the directory from which it's running is the right one. Which in this case it's /ROOT/OPENSOURCE . If it's not, then it asks if the user wants to move the directory into the correct place. Doing this by another script /OPENSOURCE/MODULES/MOVE.SH.
I have this variable to get the script launching dir:
spath="$( cd "$( dirname $0 )" && pwd )"
Now since the script will not be installed on the right directory, I need to run MOVE.SH which is in the MODULES directory inside OPENSOURCE. I can't get this done.
Code:
# check if script is on correct directory
if [ "$rpath" = "$spath" ]; then
Colors;
echo ${RedF}[x] [WAIT]${YellowF} Checking directory: ${Reset};
sleep 1
echo ${BlueF}[*] [Directory]:${GreenF} OK ${Reset};
else
Colors;
echo ${RedF}[x] [WAIT]${YellowF} Checking directory: ${Reset};
sleep 1
echo ${BlueF}[*] [Directory]:${RedF} FAILED: This may cause a script malfunction ${Reset};
read -p "[!] Move script directory to right directory {y|n}:" pass
if test "$pass" = "y"
then
echo ${BlueF}[*] [Directory]: ${GreenF}Ok. Moving script to new directory${Reset};
sleep 1
---- COMMAND WILL BE HERE ----
else
echo ${BlueF}[*] [Directory]: ${YellowF}Ok not moving ${Reset};
fi
fi
How can I do it ?
I'm not sure I 100% understand the question, but I think you might just be looking for the mysterious "." command, which will run another script.
Example:
test.sh:
#!/bin/bash
echo running other script $1
. $1
echo done
test2.sh:
#!/bin/bash
echo I am the other script
Run it:
> ./test.sh test2.sh
running other script test2.sh
I am the other script
done
Ok so I have written a .sh file in Linux Ubuntu and it works perfectly. However on a Mac it always returns that the file was not found even when it is in the same directory. Can anyone help me out?
.sh file:
if [ ! -f file-3*.jar ]; then
echo "[INFO] jar could not be found."
exit
fi
Just thought I'd add, this isn't for more than one file, it's for a file that is renamed to multiple endings.
In a comment to #Paul R's answer, you said "The shell script is also in the same directory as the jar file. So they can just double click it after assigning SH files to open with terminal by default." I suspect that's the problem -- when you run a shell script by double-clicking it, it runs with the working directory set to the user's home directory, not the directory where the script's located. You can work around this by having the script cd to the directory it's in:
cd "$(dirname "$BASH_SOURCE")"
EDIT: $BASH_SOURCE is, of course, a bash extension not available in other shells. If your script can't count on running in bash, use this instead:
case "$0" in
*/*)
cd "$(dirname "$0")" ;;
*)
me="$(which "$0")"
if [ -n "$me" ]; then
cd "$(dirname "$me")"
else
echo "Can't locate script directory" >&2
exit 1
fi ;;
esac
BTW, the construct [ ! -f file-3*.jar ] makes me nervous, since it'll fail bizarrely if there's ever more than one matching file. (I know, that's not supposed to happen; but things that aren't supposed to happen have any annoying tendency to happen anyway.) I'd use this instead:
matchfiles=(file-3*.jar)
if [ ! -f "${matchfiles[0]}" ]; then
...
Again, if you can't count on bash extensions, here's an alternative that should work in any POSIX shell:
if [ ! -f "$(echo file-3*.jar)" ]; then
Note that this will fail (i.e. act as though the file didn't exist) if there's more than one match.
I think the problem lies elsewhere, as the script works as expected on Mac OS X here:
$ if [ ! -f file-3*.jar ]; then echo "[INFO] jar could not be found."; fi
[INFO] jar could not be found.
$ touch file-302.jar
$ if [ ! -f file-3*.jar ]; then echo "[INFO] jar could not be found."; fi
$
Perhaps your script is being run under the wrong shell, or in the wrong working directory ?
It's not that it doesn't work for you, it doesn't work for your users? The default shell for OS X has changed over the years (see this post) - but it looks like your comment says you have the #! in place.
Are you sure that your users have the JAR file in the right place? Perhaps it's not the script being wrong as much as it's telling you the correct answer - the required file is missing from where the script is being run.
This isn't so much an answer, as a strategy: consider some serious logging. Echo messages such as "[INFO] jar could not be found." both to the screen and to a log file, then add extra logging, such as the values of $PWD, $SHELL and $0 to the log. Then, when your customers/co-workers try to run the script and fail, they can email the log to you.
I would probably use something like
screenlog() {
echo "$*"
echo "$*" >> $LOGFILE
}
log() {
echo "$*" >> $LOGFILE
}
Define $LOGFILE at the top of your script. Then pepper your script with statements like screenlog "[INFO] jar could not be found." or log "\$PWD: $PWD".
I am attempting to write a bash script that changes directory and then runs an existing script in the new working directory.
This is what I have so far:
#!/bin/bash
cd /path/to/a/folder
./scriptname
scriptname is an executable file that exists in /path/to/a/folder - and (needless to say), I do have permission to run that script.
However, when I run this mind numbingly simple script (above), I get the response:
scriptname: No such file or directory
What am I missing?! the commands work as expected when entered at the CLI, so I am at a loss to explain the error message. How do I fix this?
Looking at your script makes me think that the script you want to launch a script which is locate in the initial directory. Since you change you directory before executing it won't work.
I suggest the following modified script:
#!/bin/bash
SCRIPT_DIR=$PWD
cd /path/to/a/folder
$SCRIPT_DIR/scriptname
cd /path/to/a/folder
pwd
ls
./scriptname
which'll show you what it thinks it's doing.
I usually have something like this in my useful script directory:
#!/bin/bash
# Provide usage information if not arguments were supplied
if [[ "$#" -le 0 ]]; then
echo "Usage: $0 <executable> [<argument>...]" >&2
exit 1
fi
# Get the executable by removing the last slash and anything before it
X="${1##*/}"
# Get the directory by removing the executable name
D="${1%$X}"
# Check if the directory exists
if [[ -d "$D" ]]; then
# If it does, cd into it
cd "$D"
else
if [[ "$D" ]]; then
# Complain if a directory was specified, but does not exist
echo "Directory '$D' does not exist" >&2
exit 1
fi
fi
# Check if the executable is, well, executable
if [[ -x "$X" ]]; then
# Run the executable in its directory with the supplied arguments
exec ./"$X" "${#:2}"
else
# Complain if the executable is not a valid
echo "Executable '$X' does not exist in '$D'" >&2
exit 1
fi
Usage:
$ cdexec
Usage: /home/archon/bin/cdexec <executable> [<argument>...]
$ cdexec /bin/ls ls
ls
$ cdexec /bin/xxx/ls ls
Directory '/bin/xxx/' does not exist
$ cdexec /ls ls
Executable 'ls' does not exist in '/'
One source of such error messages under those conditions is a broken symlink.
However, you say the script works when run from the command line. I would also check to see whether the directory is a symlink that's doing something other than what you expect.
Does it work if you call it in your script with the full path instead of using cd?
#!/bin/bash
/path/to/a/folder/scriptname
What about when called that way from the command line?