I have written a Bash script that takes an input file as an argument and reads it.
This file contains some paths (relative to its location) to other files.
I would like the script to go to the folder containing the input file, to execute further commands.
In Linux, how do I get the folder (and just the folder) from an input file?
To get the full path use:
readlink -f relative/path/to/file
To get the directory of a file:
dirname relative/path/to/file
You can also combine the two:
dirname $(readlink -f relative/path/to/file)
If readlink -f
is not available on your system you can use this * :
function myreadlink() {
(
cd "$(dirname $1)" # or cd "${1%/*}"
echo "$PWD/$(basename $1)" # or echo "$PWD/${1##*/}"
)
}
Note that if you only need to move to a directory of a file specified as a relative path, you don't need to know the absolute path, a relative path is perfectly legal, so just use:
cd $(dirname relative/path/to/file)
if you wish to go back (while the script is running) to the original path, use pushd
instead of cd
, and popd
when you are done.
While myreadlink
above is good enough in the context of this question, it has some limitation relative to the readlink
tool suggested above. 虽然上面的myreadlink
在这个问题的上下文中已经足够好了,但它相对于上面建议的readlink
工具有一些限制。 For example it doesn't correctly follow a link to a file with different basename
.
This will work for both file and folder:
absPath(){
if [[ -d "$1" ]]; then
cd "$1"
echo "$(pwd -P)"
else
cd "$(dirname "$1")"
echo "$(pwd -P)/$(basename "$1")"
fi
}
$cat abs.sh
#!/bin/bash
echo "$(cd "$(dirname "$1")"; pwd -P)"
Some explanations:
"$1"
dirname "$1"
cd "$(dirname "$1");
into this relative dirpwd -P
and get absolute path. The -P
option will avoid symlinks echo
itThen run your script:
abs.sh your_file.txt
Try our new Bash library product realpath-lib over at GitHub that we have given to the community for free and unencumbered use. It's clean, simple and well documented so it's great to learn from. You can do:
get_realpath <absolute|relative|symlink|local file path>
This function is the core of the library:
if [[ -f "$1" ]]
then
# file *must* exist
if cd "$(echo "${1%/*}")" &>/dev/null
then
# file *may* not be local
# exception is ./file.ext
# try 'cd .; cd -;' *works!*
local tmppwd="$PWD"
cd - &>/dev/null
else
# file *must* be local
local tmppwd="$PWD"
fi
else
# file *cannot* exist
return 1 # failure
fi
# reassemble realpath
echo "$tmppwd"/"${1##*/}"
return 0 # success
}
It's Bash 4+, does not require any dependencies and also provides get_dirname, get_filename, get_stemname and validate_path.
Problem with the above answer comes with files input with "./" like "./my-file.txt"
Workaround (of many):
myfile="./somefile.txt"
FOLDER="$(dirname $(readlink -f "${ARG}"))"
echo ${FOLDER}
I have been using readlink -f works on linux
so
FULL_PATH=$(readlink -f filename)
DIR=$(dirname $FULL_PATH)
PWD=$(pwd)
cd $DIR
#<do more work>
cd $PWD
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.