I am using this in a Bash script to get the path where I have run the script from. It is necessary for double clicking a .command file in OS X.
#!/bin/bash
BASEDIR=$(dirname $0)
cd $BASEDIR
The problem is it doesn't work when the path has spaces. How might you fix that?
You have to use quotes:
#!/bin/bash
BASEDIR=$(dirname $0)
cd "$BASEDIR"
I'm using this to start my plackup server, my: "run.command"
DIR=`dirname "$0"`
cd "$DIR"
plackup -r
This can be a doozy. None of the prior answers will resolve symlinks. This one should be reasonably portable (double-checked with dash and bash), and will traverse symlinks with whitespace in the path(s):
#!/bin/sh # dash bash ksh # !zsh (issues). G. Nixon, 12/2013. Public domain.
## 'linkread' or 'fullpath' or (you choose) is a little tool to recursively
## dereference symbolic links (ala 'readlink') until the originating file
## is found. This is effectively the same function provided in stdlib.h as
## 'realpath' and on the command line in GNU 'readlink -f'.
##===-------------------------------------------------------------------===##
for argv; do :; done # Last parameter on command line, for options parsing.
## Error messages. Use functions so that we can sub in when the error occurs.
recurses(){ printf "Self-referential:\n\t$argv ->\n\t$argv\n" ;}
dangling(){ printf "Broken symlink:\n\t$argv ->\n\t"$(readlink "$argv")"\n" ;}
errnoent(){ printf "No such file: "$@"\n" ;} # Borrow a horrible signal name.
# Probably best not to install as 'pathfull', if you can avoid it.
pathfull(){ cd "$(dirname "$@")"; link="$(readlink "$(basename "$@")")"
## 'test and 'ls' report different status for bad symlinks, so we use this.
if [ ! -e "$@" ]; then if $(ls -d "$@" 2>/dev/null) 2>/dev/null; then
errnoent 1>&2; exit 1; elif [ ! -e "$@" -a "$link" = "$@" ]; then
recurses 1>&2; exit 1; elif [ ! -e "$@" ] && [ ! -z "$link" ]; then
dangling 1>&2; exit 1; fi
fi
## Not a link, but there might be one in the path, so 'cd' and 'pwd'.
if [ -z "$link" ]; then if [ "$(dirname "$@" | cut -c1)" = '/' ]; then
printf "$@\n"; exit 0; else printf "$(pwd)/$(basename "$@")\n"; fi; exit 0
fi
## Walk the symlinks back to the origin. Calls itself recursivly as needed.
while [ "$link" ]; do
cd "$(dirname "$link")"; newlink="$(readlink "$(basename "$link")")"
case "$newlink" in
"$link") dangling 1>&2 && exit 1 ;;
'') printf "$(pwd)/$(basename "$link")\n"; exit 0 ;;
*) link="$newlink" && pathfull "$link" ;;
esac
done
printf "$(pwd)/$(basename "$newlink")\n"
}
## Demo. Install somewhere deep in the filesystem, then symlink somewhere
## else, symlink again (maybe with a different name) elsewhere, and link
## back into the directory you started in (or something.) The absolute path
## of the script will always be reported in the usage, along with "$0".
if [ -z "$argv" ]; then scriptname="$(pathfull "$0")"
# Yay ANSI l33t codes! Fancy.
printf "\n\033[3mfrom/as: \033[4m$0\033[0m\n\n\033[1mUSAGE:\033[0m "
printf "\033[4m$scriptname\033[24m [ link | file | dir ]\n\n "
printf "Recursive readlink for the authoritative file, symlink after "
printf "symlink.\n\n\n \033[4m$scriptname\033[24m\n\n "
printf " From within an invocation of a script, locate the script's "
printf "own file\n (no matter where it has been linked or "
printf "from where it is being called).\n\n"
else pathfull "$@"
fi
