I'm new to bash and I'm working on script that traverses the tar.gz file archive and in each file changes a string specified to an another string. Args of script: name of archive, searched string, target word.
My problem is that when archive name contains a space (e.g. I run script with following args: > change_strings.sh "/tmp/tmp.m7xYn5EQ2y/work/data txt" a A) I have following error:
on line if [ ! -f $filename ] ; then [: data: binary operator expected, dirname: extra operand `txt'.
Here is my code:
#!/bin/bash
filename="${1##*/}"
VAR="$1"
DIR=$(dirname ${VAR})
cd "$DIR"
if [ ! -f $filename ] ; then
echo "no such archive" >&2
exit 1
fi
if ! tar tf $filename &> /dev/null; then
echo "this is not .tar.gz archive" >&2
exit 1
fi
dir=`mktemp -dt 'test.XXXXXX'`
tar -xf $filename -C $dir #extract archive to dir
cd $dir #go to argument directory
FILES=$dir"/*"
for f in $FILES
do
sed -i "s/$2/$3/g" "$f"
done
tar -czf $filename * #create tar gz archive with files in current directory
mv -f $filename $cdir"/"$filename #move archive
rm -r $dir #remove tmp directory
The proper way to handle this is to surround your variables with double quotes.
var=/foo/bar baz
CMD $var # CMD /foo/bar baz
The above code will execute CMD on /foo/bar and baz
CMD "$var"
This will execute CMD on "/foo/bar baz". It is a best practice to always surround your variables with double quotes in most places.
Welcome to stackoverflow!
For the convenience of current and future readers, here's a small, self contained example showing the problem:
filename="my file.txt"
if [ ! -f $filename ]
then
echo "file does not exist"
fi
Here's the output we get:
$ bash file
file: line 2: [: my: binary operator expected
And here's the output we expected to get:
file does not exist
Why are they not the same?
Here's what shellcheck has to say about it:
$ shellcheck file
In file line 2:
if [ -f $filename ]
^-- SC2086: Double quote to prevent globbing and word splitting.
and indeed, if we double quote it, we get the expected output:
$ cat file
filename="my file.txt"
if [ ! -f "$filename" ]
then
echo "file does not exist"
fi
$ bash file
file does not exist
You should be double quoting all your variables.
However, you have to take care with $FILES because it contains a glob/wildcards that you want to expand along with potential spaces that you don't want to wordsplit on. The easiest way is to just not put it in a variable and instead write it out:
for f in "$dir"/*
do
...
I am trying to assign an absolute path to a variable in Bash:
#!/bin/bash
DIR= "/home/foobar"
echo "$DIR/test"
The output:
./test.sh: line 2: /home/foobar: Is a directory
/test
I don't understand what is happening there, please help me.
Remove the space before "/home/foobar":
#!/bin/bash
DIR="/home/foobar"
echo "$DIR/test"
Try in another shell.
#!/bin/sh
DIR='/home/foobar'
echo "$DIR/test"
Or if you want to check if the variable is getting initialized or not using this.
#!/bin/sh
DIR='/home/foobar'
[ -z "$DIR" ] && echo "Variable not declared" && exit
echo "$DIR/test"
The general syntax is
[ assignment=value ... ] command arguments
so you are doing an assignment of DIR= and running the command /home/foobar -- which of course isn't a valid command, but a directory; hence the error message.
Try this:
DIR=/home/foobar bash -c 'echo "DIR is \"$DIR\""' # DIR is "/home/foobar"
echo "done. DIR is now \"$DIR\"" # DIR is now ""
and you will see that DIR is assigned only during the first command, then lost.
To set it for the remainder of your script, you can do
DIR=/home/foobar
echo "DIR is now $DIR"
and if you want to expose it to child processes, you can add an export:
DIR=/home/foobar
bash -c 'echo "Before export: DIR is \"$DIR\""' # DIR is ""
export DIR
bash -c 'echo "After export: DIR is \"$DIR\""' # DIR is "/home/foobar"
i have a sh-Script with:
#!/bin/sh
dirs=( $(find . -maxdepth 1 -type d -printf '%P\n') )
echo "There are ${#dirs[#]} dirs in the current path"
let i=1
for dir in "${dirs[#]}"; do
echo "$((i++)) $dir"
done
answer=2
echo "you selected ${dirs[$answer]}!"
But i got the error:
symfonymenu.sh: Syntax error: "(" unexpected (expecting "}")
its the line ...dirs=
I like to echo all available directories in a folder that user can select it in a prompt interface.
You use features from the bash shell, so you should execute the script in bash. Change the first line to:
#!/bin/bash
/bin/sh can be any POSIX-compatible shell, for example on Ubuntu it's dash.
That's a bash script so you should make sure that you're running it with bash. Call it as bash script.sh. Also you should start your index from 0 not 1: let i=0.
In my script, I am holding the location (path) of a file as a variable.
For example, fileA
An example of its contents are
fileA=/usr/anotherfolder/somefold/"filenamehere"
However, when i call a command on the file in the script such as:
cat $fileA
or
cat "$fileA"
I get an error saying the file or directory doesn't exist. If I echo $fileA to see what the output is, and then run a cat manually from the terminal, it works fine, don't know what is going wrong. Any help?
Some debug info:
fileA='/home/jacob/Desktop/CS35L/WORK/2/hw/test3/"new"'
echo '/home/jacob/Desktop/CS35L/WORK/2/hw/test3/"new"'
/home/jacob/Desktop/CS35L/WORK/2/hw/test3/"new"
'[' '!' -r '/home/jacob/Desktop/CS35L/WORK/2/hw/test3/"new"' ']'
For these particular lines
Check for readable file
echo $fileA
if [ ! -r "$fileA" ]
then
o=`expr $o + 1`
echo "$fileA not readable."
continue
fi
If file name is new(not "new"), then change
fileA='/home/jacob/Desktop/CS35L/WORK/2/hw/test3/"new"'
to
fileA=/home/jacob/Desktop/CS35L/WORK/2/hw/test3/new
Is there an easy way I can print the full path of file.txt ?
file.txt = /nfs/an/disks/jj/home/dir/file.txt
The <command>
dir> <command> file.txt
should print
/nfs/an/disks/jj/home/dir/file.txt
Use readlink:
readlink -f file.txt
I suppose you are using Linux.
I found a utility called realpath in coreutils 8.15.
realpath -s file.txt
/data/ail_data/transformed_binaries/coreutils/test_folder_realpath/file.txt
Since the question is about how to get the full/absolute path of a file and not about how to get the target of symlinks, use -s or --no-symlinks which means don't expand symlinks.
As per #styrofoam-fly and #arch-standton comments, realpath alone doesn't check for file existence, to solve this add the e argument: realpath -e file
The following usually does the trick:
echo "$(cd "$(dirname "$1")" && pwd -P)/$(basename "$1")"
I know there's an easier way that this, but darned if I can find it...
jcomeau#intrepid:~$ python -c 'import os; print(os.path.abspath("cat.wav"))'
/home/jcomeau/cat.wav
jcomeau#intrepid:~$ ls $PWD/cat.wav
/home/jcomeau/cat.wav
On Windows:
Holding Shift and right clicking on a file in Windows Explorer gives you an option called Copy as Path.
This will copy the full path of the file to clipboard.
On Linux:
You can use the command realpath yourfile to get the full path of a file as suggested by others.
find $PWD -type f | grep "filename"
or
find $PWD -type f -name "*filename*"
If you are in the same directory as the file:
ls "`pwd`/file.txt"
Replace file.txt with your target filename.
I know that this is an old question now, but just to add to the information here:
The Linux command which can be used to find the filepath of a command file, i.e.
$ which ls
/bin/ls
There are some caveats to this; please see https://www.cyberciti.biz/faq/how-do-i-find-the-path-to-a-command-file/.
You could use the fpn (full path name) script:
% pwd
/Users/adamatan/bins/scripts/fpn
% ls
LICENSE README.md fpn.py
% fpn *
/Users/adamatan/bins/scripts/fpn/LICENSE
/Users/adamatan/bins/scripts/fpn/README.md
/Users/adamatan/bins/scripts/fpn/fpn.py
fpn is not a standard Linux package, but it's a free and open github project and you could set it up in a minute.
Works on Mac, Linux, *nix:
This will give you a quoted csv of all files in the current dir:
ls | xargs -I {} echo "$(pwd -P)/{}" | xargs | sed 's/ /","/g'
The output of this can be easily copied into a python list or any similar data structure.
echo $(cd $(dirname "$1") && pwd -P)/$(basename "$1")
This is explanation of what is going on at #ZeRemz's answer:
This script get relative path as argument "$1"
Then we get dirname part of that path (you can pass either dir or file to this script): dirname "$1"
Then we cd "$(dirname "$1") into this relative dir
&& pwd -P and get absolute path for it. -P option will avoid all symlinks
After that we append basename to absolute path: $(basename "$1")
As final step we echo it
You may use this function. If the file name is given without relative path, then it is assumed to be present in the current working directory:
abspath() { old=`pwd`;new=$(dirname "$1");if [ "$new" != "." ]; then cd $new; fi;file=`pwd`/$(basename "$1");cd $old;echo $file; }
Usage:
$ abspath file.txt
/I/am/in/present/dir/file.txt
Usage with relative path:
$ abspath ../../some/dir/some-file.txt
/I/am/in/some/dir/some-file.txt
With spaces in file name:
$ abspath "../../some/dir/another file.txt"
/I/am/in/some/dir/another file.txt
You can save this in your shell.rc or just put in console
function absolute_path { echo "$PWD/$1"; }
alias ap="absolute_path"
example:
ap somefile.txt
will output
/home/user/somefile.txt
I was surprised no one mentioned located.
If you have the locate package installed, you don't even need to be in the directory with the file of interest.
Say I am looking for the full pathname of a setenv.sh script. This is how to find it.
$ locate setenv.sh
/home/davis/progs/devpost_aws_disaster_response/python/setenv.sh
/home/davis/progs/devpost_aws_disaster_response/webapp/setenv.sh
/home/davis/progs/eb_testy/setenv.sh
Note, it finds three scripts in this case, but if I wanted just one I
would do this:
$ locate *testy*setenv.sh
/home/davis/progs/eb_testy/setenv.sh
This solution uses commands that exist on Ubuntu 22.04, but generally exist on most other Linux distributions, unless they are just to hardcore for s'mores.
The shortest way to get the full path of a file on Linux or Mac is to use the ls command and the PWD environment variable.
<0.o> touch afile
<0.o> pwd
/adir
<0.o> ls $PWD/afile
/adir/afile
You can do the same thing with a directory variable of your own, say d.
<0.o> touch afile
<0.o> d=/adir
<0.o> ls $d/afile
/adir/afile
Notice that without flags ls <FILE> and echo <FILE> are equivalent (for valid names of files in the current directory), so if you're using echo for that, you can use ls instead if you want.
If the situation is reversed, so that you have the full path and want the filename, just use the basename command.
<0.o> touch afile
<0.o> basename $PWD/afile
afile
In a similar scenario, I'm launching a cshell script from some other location. For setting the correct absolute path of the script so that it runs in the designated directory only, I'm using the following code:
set script_dir = `pwd`/`dirname $0`
$0 stores the exact string how the script was executed.
For e.g. if the script was launched like this: $> ../../test/test.csh,
$script_dir will contain /home/abc/sandbox/v1/../../test
For Mac OS X, I replaced the utilities that come with the operating system and replaced them with a newer version of coreutils. This allows you to access tools like readlink -f (for absolute path to files) and realpath (absolute path to directories) on your Mac.
The Homebrew version appends a 'G' (for GNU Tools) in front of the command name -- so the equivalents become greadlink -f FILE and grealpath DIRECTORY.
Instructions for how to install the coreutils/GNU Tools on Mac OS X through Homebrew can be found in this StackExchange arcticle.
NB: The readlink -f and realpath commands should work out of the box for non-Mac Unix users.
I like many of the answers already given, but I have found this really useful, especially within a script to get the full path of a file, including following symlinks and relative references such as . and ..
dirname `readlink -e relative/path/to/file`
Which will return the full path of the file from the root path onwards.
This can be used in a script so that the script knows which path it is running from, which is useful in a repository clone which could be located anywhere on a machine.
basePath=`dirname \`readlink -e $0\``
I can then use the ${basePath} variable in my scripts to directly reference other scripts.
Hope this helps,
Dave
This worked pretty well for me. It doesn't rely on the file system (a pro/con depending on need) so it'll be fast; and, it should be portable to most any *NIX. It does assume the passed string is indeed relative to the PWD and not some other directory.
function abspath () {
echo $1 | awk '\
# Root parent directory refs to the PWD for replacement below
/^\.\.\// { sub("^", "./") } \
# Replace the symbolic PWD refs with the absolute PWD \
/^\.\// { sub("^\.", ENVIRON["PWD"])} \
# Print absolute paths \
/^\// {print} \'
}
This is naive, but I had to make it to be POSIX compliant. Requires permission to cd into the file's directory.
#!/bin/sh
if [ ${#} = 0 ]; then
echo "Error: 0 args. need 1" >&2
exit 1
fi
if [ -d ${1} ]; then
# Directory
base=$( cd ${1}; echo ${PWD##*/} )
dir=$( cd ${1}; echo ${PWD%${base}} )
if [ ${dir} = / ]; then
parentPath=${dir}
else
parentPath=${dir%/}
fi
if [ -z ${base} ] || [ -z ${parentPath} ]; then
if [ -n ${1} ]; then
fullPath=$( cd ${1}; echo ${PWD} )
else
echo "Error: unsupported scenario 1" >&2
exit 1
fi
fi
elif [ ${1%/*} = ${1} ]; then
if [ -f ./${1} ]; then
# File in current directory
base=$( echo ${1##*/} )
parentPath=$( echo ${PWD} )
else
echo "Error: unsupported scenario 2" >&2
exit 1
fi
elif [ -f ${1} ] && [ -d ${1%/*} ]; then
# File in directory
base=$( echo ${1##*/} )
parentPath=$( cd ${1%/*}; echo ${PWD} )
else
echo "Error: not file or directory" >&2
exit 1
fi
if [ ${parentPath} = / ]; then
fullPath=${fullPath:-${parentPath}${base}}
fi
fullPath=${fullPath:-${parentPath}/${base}}
if [ ! -e ${fullPath} ]; then
echo "Error: does not exist" >&2
exit 1
fi
echo ${fullPath}
This works with both Linux and Mac OSX:
echo $(pwd)$/$(ls file.txt)
find / -samefile file.txt -print
Will find all the links to the file with the same inode number as file.txt
adding a -xdev flag will avoid find to cross device boundaries ("mount points"). (But this will probably cause nothing to be found if the find does not start at a directory on the same device as file.txt)
Do note that find can report multiple paths for a single filesystem object, because an Inode can be linked by more than one directory entry, possibly even using different names. For instance:
find /bin -samefile /bin/gunzip -ls
Will output:
12845178 4 -rwxr-xr-x 2 root root 2251 feb 9 2012 /bin/uncompress
12845178 4 -rwxr-xr-x 2 root root 2251 feb 9 2012 /bin/gunzip
Usually:
find `pwd` | grep <filename>
Alternatively, just for the current folder:
find `pwd` -maxdepth 1 | grep <filename>
This will work for both file and folder:
getAbsolutePath(){
[[ -d $1 ]] && { cd "$1"; echo "$(pwd -P)"; } ||
{ cd "$(dirname "$1")" || exit 1; echo "$(pwd -P)/$(basename "$1")"; }
}
Another Linux utility, that does this job:
fname <file>
For Mac OS, if you just want to get the path of a file in the finder, control click the file, and scroll down to "Services" at the bottom. You get many choices, including "copy path" and "copy full path". Clicking on one of these puts the path on the clipboard.
fp () {
PHYS_DIR=`pwd -P`
RESULT=$PHYS_DIR/$1
echo $RESULT | pbcopy
echo $RESULT
}
Copies the text to your clipboard and displays the text on the terminal window.
:)
(I copied some of the code from another stack overflow answer but cannot find that answer anymore)
In Mac OSX, do the following steps:
cd into the directory of the target file.
Type either of the following terminal commands.
Terminal
ls "`pwd`/file.txt"
echo $(pwd)/file.txt
Replace file.txt with your actual file name.
Press Enter
you#you:~/test$ ls
file
you#you:~/test$ path="`pwd`/`ls`"
you#you:~/test$ echo $path
/home/you/test/file
Beside "readlink -f" , another commonly used command:
$find /the/long/path/but/I/can/use/TAB/to/auto/it/to/ -name myfile
/the/long/path/but/I/can/use/TAB/to/auto/it/to/myfile
$
This also give the full path and file name at console
Off-topic: This method just gives relative links, not absolute. The readlink -f command is the right one.