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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Commands tagged PATH from sorted by
Terminal - Commands tagged PATH - 35 results
echo $PATH | tr -s ':' '\n'
if [[ ":$PATH:" != *":$dir:"* ]]; then PATH=${PATH}:$dir; fi
2013-08-11 01:19:13
User: dmmst19
Tags: bash PATH $PATH

Sometimes in a script you want to make sure that a directory is in the path, and add it in if it's not already there. In this example, $dir contains the new directory you want to add to the path if it's not already present.

There are multiple ways to do this, but this one is a nice clean shell-internal approach. I based it on http://stackoverflow.com/a/1397020.

You can also do it using tr to separate the path into lines and grep -x to look for exact matches, like this:

if ! $(echo "$PATH" | tr ":" "\n" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi

which I got from http://stackoverflow.com/a/5048977.

Or replace the "echo | tr" part with a shell parameter expansion, like

if ! $(echo "${PATH//:/$'\n'}" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi

which I got from http://www.commandlinefu.com/commands/view/3209/.

There are also other more regex-y ways to do it, but I find the ones listed here easiest to follow.

Note some of this is specific to the bash shell.

convert_path2uri () { echo -n 'file://'; echo -n "$1" | perl -pe 's/([^a-zA-Z0-9_\/.])/sprintf("%%%.2x", ord($1))/eg' ;} #convert2uri '/tmp/a b' ### convert file path to URI
2013-07-01 08:54:45
User: totti
Functions: echo file perl
Tags: encoding PATH url

Really helpfull when play with files having spaces an other bad name. Easy to store and access names and path in just a field while saving it in a file.

This format (URL) is directly supported by nautilus and firefox (and other browsers)

echo "$: << '.'" >> $IRBRC
echo -e ${PATH//:/\\n}
realpath -s <filename>
2011-03-02 23:40:57
User: kalaxy
Tags: PATH

Will convert relative paths into absolute paths.

bind '"\C-e":"\eb `which \ef`\e\C-e"'
2011-01-26 16:11:52
User: jennings6k

Tested with bash v4.1.5 on ubuntu 10.10


as written above, only works for programs with no file extention (i.e 'proggy', but not 'proggy.sh')

because \eb maps to readine function backward-word rather then shell-backward-word (which

is unbinded by default on ubuntu), and correspondingly for \ef.

if you're willing to have Ctrl-f and Ctrl-g taken up too , you can insert the following lines

into ~/.inputrc, in which case invoking Ctrl-e will do the right thing both for "proggy" and "proggy.sh".

-- cut here --



"\C-e":"\C-f`which \C-g`\e\C-e"

-- cut here --

perl -le 'chomp($w=`which $ARGV[0]`);$_=`file $w`;while(/link\b/){chomp($_=(split/`/,$_)[1]);chop$_;$w.=" -> $_";$_=`file $_`;}print "\n$w";' COMMAND_NAME
2010-07-30 19:26:35
User: dbbolton
Functions: perl

This will show you any links that a command follows (unlike 'file -L'), as well as the ultimate binary or script.

Put the name of the command at the very end; this will be passed to perl as the first argument.

For obvious reasons, this doesn't work with aliases or functions.

rp() { local p; eval p=":\$$1:"; export $1=${p//:$2:/:}; }; ap() { rp "$1" "$2"; eval export $1=\$$1$2; }; pp() { rp "$1" "$2"; eval export $1=$2:\$$1; }
2010-07-15 18:52:01
User: cout
Functions: eval export

I used to do a lot of path manipulation to set up my development environment (PATH, LD_LIBRARY_PATH, etc), and one part of my environment wasn't always aware of what the rest of the environment needed in the path. Thus resetting the entire PATH variable wasn't an option; modifying it made sense.

The original version of the functions used sed, which turned out to be really slow when called many times from my bashrc, and it could take up to 10 seconds to login. Switching to parameter substitution sped things up significantly.

The commands here don't clean up the path when they are done (so e.g. the path gets cluttered with colons). But the code is easy to read for a one-liner.

The full function looks like this:

remove_path() { eval PATHVAL=":\$$1:" PATHVAL=${PATHVAL//:$2:/:} # remove $2 from $PATHVAL PATHVAL=${PATHVAL//::/:} # remove any double colons left over PATHVAL=${PATHVAL#:} # remove colons from the beginning of $PATHVAL PATHVAL=${PATHVAL%:} # remove colons from the end of $PATHVAL export $1="$PATHVAL" } append_path() { remove_path "$1" "$2" eval PATHVAL="\$$1" export $1="${PATHVAL}:$2" } prepend_path() { remove_path "$1" "$2" eval PATHVAL="\$$1" export $1="$2:${PATHVAL}" }

I tried using regexes to make this into a cleaner one-liner, but remove_path ended up being cryptic and not working as well:

rp() { eval "[[ ::\$$1:: =~ ^:+($2:)?((.*):$2:)?(.*):+$ ]]"; export $1=${BASH_REMATCH[3]}:${BASH_REMATCH[4]}; };
unset MANPATH; manpath >/dev/null
2010-07-02 19:45:27
Functions: manpath unset
Tags: man PATH

If I type 'man something', I want it to find the manpage in the same order as my PATH.

You can add something like this to your .bashrc


# Add my MacPorts, my personal utilities and my company utilities to my PATH.

export PATH=$PATH:/opt/local/bin:$HOME/bin:/our_company_utils/bin/

# Now set the manpath based on the PATH, after man(1) parses man.conf

# - No need to modify man.conf or manually modify MANPATH_MAP

# - Works on Linux, FreeBSD & Darwin, unlike /etc/manpaths.d/

# Must unset MANPATH first. MANPATH is set on some systems automatically (Mac),

# which causes manpath to ignore the values of PATH like /opt/local/bin (MacPorts).

# Also MANPATH may be deprecated. See "SEARCH PATH FOR MANUAL PAGES" in man(1)


# manpath acts differently on Solaris, FreeBSD, MacOSX & GNU. This works everywhere.

manpath >/dev/null


Note that MacOSX, FreeBSD & Linux have fancier ways to do some of this. (e.g. 'man --path' or 'man -q'), but this command is more universal and should work everywhere.

hash -r
2010-06-18 11:16:23
User: dpoblador
Functions: hash
Tags: PATH hash $PATH

i.e.: Useful if you add ~/bin to your $PATH and you want to override locations of previously ran commands and you don't want to log out and log back in to be able to use them.

function wherepath () { for DIR in `echo $PATH | tr ":" "\n" | awk '!x[$0]++ {print $0}'`; do ls ${DIR}/$1 2>/dev/null; done }
2010-04-02 20:32:36
User: mscar
Functions: awk ls tr
Tags: find locate PATH

The wherepath function will search all the directories in your PATH and print a unique list of locations in the order they are first found in the PATH. (PATH often has redundant entries.) It will automatically use your 'ls' alias if you have one or you can hardcode your favorite 'ls' options in the function to get a long listing or color output for example.


'whereis' only searches certain fixed locations.

'which -a' searches all the directories in your path but prints duplicates.

'locate' is great but isn't installed everywhere (and it's often too verbose).

printf ${PATH//:/\\n}
ls -d $(echo ${PATH//:/ }) > /dev/null
type <command>
whereis command
which command
echo -e ${PATH//:/\\n} | less
2010-01-09 23:25:02
User: nicoulaj
Functions: echo
Tags: PATH

Display the $PATH with one line per entry, in a pager.

printf "%s\n" ${PATH//:/\/* }
in bash hit "tab" twice and answer y
absolute_path () { readlink -f "$1"; };
path+=( /sbin /usr/sbin /usr/local/sbin ); path=( ${(u)path} );
2009-10-31 02:32:25
User: atoponce
Tags: sudo zsh PATH sbin

On RHEL, Fedora and CentOS systems, and maybe others, the sbin directories aren't in the user's $PATH. For those systems that use 'sudo', this can be inconvenient typing the full path all the time. As a result, you can easily take advantage of adding the sbin directories to your PATH by adding this simple line to you .zshrc.

script_path=$(cd $(dirname $0);pwd)
2009-10-14 16:04:03
User: jgc
Functions: cd dirname
Tags: cd pwd PATH

Another way of doing it that's a bit clearer. I'm a fan of readable code.

(IFS=:;for p in $PATH; do test -d $p || echo $p; done)
2009-09-19 17:51:06
User: haivu
Functions: echo test
Tags: bash PATH

I often need to know of my directory in the PATH, which one DOES NOT exist. This command answers that question

* This command uses only bash's built-in commands

* The parentheses spawn a new sub shell to prevent the modification of the IFS (input field separator) variable in the current shell