shell get - bash/fish command to print absolute path to a file




of directory (15)

Question: is there a simple sh/bash/zsh/fish/... command to print the absolute path of whichever file I feed it?

Usage case: I'm in directory /a/b and I'd like to print the full path to file c on the command-line so that I can easily paste it into another program: /a/b/c. Simple, yet a little program to do this could probably save me 5 or so seconds when it comes to handling long paths, which in the end adds up. So it surprises me that I can't find a standard utility to do this — is there really none?

Here's a sample implementation, abspath.py:

#!/usr/bin/python
# Author: Diggory Hardy <[email protected]>
# Licence: public domain
# Purpose: print the absolute path of all input paths

import sys
import os.path
if len(sys.argv)>1:
    for i in range(1,len(sys.argv)):
        print os.path.abspath( sys.argv[i] )
    sys.exit(0)
else:
    print >> sys.stderr, "Usage: ",sys.argv[0]," PATH."
    sys.exit(1)

Answers

Try realpath.

$ realpath example.txt
/home/username/example.txt

$ readlink -m FILE
/path/to/FILE

This is better than readlink -e FILE or realpath, because it works even if the file doesn't exist.


Forget about readlink and realpath which may or may not be installed on your system.

Expanding on dogbane's answer above here it is expressed as a function:

#!/bin/bash
get_abs_filename() {
  # $1 : relative filename
  echo "$(cd "$(dirname "$1")" && pwd)/$(basename "$1")"
}

you can then use it like this:

myabsfile=$(get_abs_filename "../../foo/bar/file.txt")

How and why does it work?

The solution exploits the fact that the Bash built-in pwd command will print the absolute path of the current directory when invoked without arguments.

Why do I like this solution ?

It is portable and doesn't require neither readlink or realpath which often does not exist on a default install of a given Linux/Unix distro.

What if dir doesn't exist?

As given above the function will fail and print on stderr if the directory path given does not exist. This may not be what you want. You can expand the function to handle that situation:

#!/bin/bash
get_abs_filename() {
  # $1 : relative filename
  if [ -d "$(dirname "$1")" ]; then
    echo "$(cd "$(dirname "$1")" && pwd)/$(basename "$1")"
  fi
}

Now it will return an empty string if one the parent dirs do not exist.

How do you handle trailing '..' or '.' in input ?

Well, it does give an absolute path in that case, but not a minimal one. It will look like:

/Users/bob/Documents/..

If you want to resolve the '..' you will need to make the script like:

get_abs_filename() {
  # $1 : relative filename
  filename=$1
  parentdir=$(dirname "${filename}")

  if [ -d "${filename}" ]; then
      echo "$(cd "${filename}" && pwd)"
  elif [ -d "${parentdir}" ]; then
    echo "$(cd "${parentdir}" && pwd)/$(basename "${filename}")"
  fi
}

I have placed the following script on my system & I call it as a bash alias for when I want to quickly grab the full path to a file in the current dir:

#!/bin/bash
/usr/bin/find "$PWD" -maxdepth 1 -mindepth 1 -name "$1"

I am not sure why, but, on OS X when called by a script "$PWD" expands to the absolute path. When the find command is called on the command line, it doesn't. But it does what I want... enjoy.


If you don't have readlink or realpath utilities than you can use following function which works in bash and zsh (not sure about the rest).

abspath () { case "$1" in /*)printf "%s\n" "$1";; *)printf "%s\n" "$PWD/$1";; esac; }

This also works for nonexistent files (as does the python function os.path.abspath).

Unfortunately abspath ./../somefile doesn't get rid of the dots.


#! /bin/sh
echo "$(cd "$(dirname "$1")"; pwd -P)/$(basename "$1")"

For directories dirname gets tripped for ../ and returns ./.

nolan6000's function can be modified to fix that:

get_abs_filename() {
  # $1 : relative filename
  if [ -d "${1%/*}" ]; then
    echo "$(cd ${1%/*}; pwd)/${1##*/}"
  fi
}

The dogbane answer with the description what is coming on:

#! /bin/sh
echo "$(cd "$(dirname "$1")"; pwd)/$(basename "$1")"

Explanation:

  1. This script get relative path as argument "$1"
  2. Then we get dirname part of that path (you can pass either dir or file to this script): dirname "$1"
  3. Then we cd "$(dirname "$1") into this relative dir and get absolute path for it by running pwd shell command
  4. After that we append basename to absolute path: $(basename "$1")
  5. As final step we echo it

Hey guys I know it's an old thread but I am just posting this for reference to anybody else who visited this like me. If i understood the question correctly, I think the locate $filename command. It displays the absolute path of the file supplied, but only if it exists.


#! /bin/bash

file="[email protected]"
realpath "$file" 2>/dev/null || eval realpath $(echo $file | sed 's/ /\\ /g')

This makes up for the shortcomings of realpath, store it in a shell script fullpath. You can now call:

$ cd && touch a\ a && rm A 2>/dev/null 
$ fullpath "a a"
/home/user/a a
$ fullpath ~/a\ a
/home/user/a a
$ fullpath A
A: No such file or directory.

An alternative to get the absolute path in Ruby:

realpath() {ruby -e "require 'Pathname'; puts Pathname.new('$1').realpath.to_s";}

Works with no arguments (current folder) and relative and absolute file or folder path as agument.


This is not an answer to the question, but for those who does scripting:

echo `cd "$1" 2>/dev/null&&pwd||(cd "$(dirname "$1")";pwd|sed "s|/*\$|/${1##*/}|")`

it handles / .. ./ etc correctly. I also seems to work on OSX


Try readlink which will resolve symbolic links:

readlink -e /foo/bar/baz

This relative path to absolute path converter shell function

  • requires no utilities (just cd and pwd)
  • works for directories and files
  • handles .. and .
  • handles spaces in dir or filenames
  • requires that file or directory exists
  • returns nothing if nothing exists at the given path
  • handles absolute paths as input (passes them through essentially)

Code:

function abspath() {
    # generate absolute path from relative path
    # $1     : relative filename
    # return : absolute path
    if [ -d "$1" ]; then
        # dir
        (cd "$1"; pwd)
    elif [ -f "$1" ]; then
        # file
        if [[ $1 = /* ]]; then
            echo "$1"
        elif [[ $1 == */* ]]; then
            echo "$(cd "${1%/*}"; pwd)/${1##*/}"
        else
            echo "$(pwd)/$1"
        fi
    fi
}

Sample:

# assume inside /parent/cur
abspath file.txt        => /parent/cur/file.txt
abspath .               => /parent/cur
abspath ..              => /parent
abspath ../dir/file.txt => /parent/dir/file.txt
abspath ../dir/../dir   => /parent/dir          # anything cd can handle
abspath doesnotexist    =>                      # empty result if file/dir does not exist
abspath /file.txt       => /file.txt            # handle absolute path input

Note: This is based on the answers from nolan6000 and bsingh, but fixes the file case.

I also understand that the original question was about an existing command line utility. But since this seems to be THE question on for that including shell scripts that want to have minimal dependencies, I put this script solution here, so I can find it later :)


#!/bin/bash
#
# Change the file name from "test" to desired input file 
# (The comments in bash are prefixed with #'s)
for x in $(cat test.txt)
do
    echo $x
done




bash shell path