Cfrgtkky

In addition (to Kusalananda's answer):

#! /bin/bash 



echo "(bash/ksh): ${@: -1}"

echo "(bash 3.x+): ${!#}"

echo "(bash 3.x+): $BASH_ARGV"

echo "(bash 3.x+/ksh): ${@:$#}"

echo "(bash 3.x+): ${BASH_ARGV[0]}"

and if you worry about portability:

#!/bin/bash



penultimate=''

ultimate=''



for p in "$@" ; do

    penultimate="$ultimate"

    ultimate="$p"

done



echo "penultimate=$penultimate"

echo "ultimate=$ultimate"

To get any argument from bash script, you can use slicing:

#!/bin/bash



# Get 3rd element from the end

from_end1=3

# Get last element

from_end2=1



# Get slice of array [end - from_end1 : end ] of length 1

echo "${@: -$from_end1: 1}"

echo "${@: -$from_end2: 1}"

You can also use this to get Nth element:

# Get 2nd element

from_beginning=2



echo "${@: $from_beginning: 1}"

Remember to check for length; this might return your program's name or an empty string.

In bash (release 4.3+), you may assign the passed parameters to an array and access the last one by the index -1:

#!/bin/bash



params=( "$@" )

printf 'The last parameter given to the script is %sn' "${params[-1]}"



foo () {

    params=( "$@" )

    printf 'The last parameter given to the function is %sn' "${params[-1]}"

}

In general, negative indexes into arrays accesses the elements from the end of the array.

Portable sh, not bash-specific, and without O(n) loops:

eval x=$$(($#-1))

The -1 yields the penultimate argument; replace it with the position you want relative to the end, or drop it entirely if you want the very last one.

In zsh, the most natural thing, I think, would be:

echo "ultimate: ${@[$#]}"

echo "ultimate: ${@[-1]}"

echo "penultimate: ${@[-2]}"

echo "penultimate: ${@[$(($# - 1))]}"

The clasic solutions for POSIX shells (which also work on ksh, zsh or bash) are:

 for last do :;done; echo "last=$last"

 eval "last=$$#"; echo "last=$last"

For newer shells (ksh93,zsh,bash):

 echo "last=${@: -1}"

 echo "last=${@:(-1)}"

 echo "last=${@:~0}"

 echo "last=${@:$#}"

Only for:

bash echo "last=${!#}"
bash echo "last=$BASH_ARGV"
zsh echo "last=${@[-1]}"
zsh echo "last=${@[#]}"

For the penultimate argument:

 for arg do penultimate=$ultimate; ultimate=$arg; done; echo "$penultimate"

 eval penultimate=$$((#-1))

 echo "${@:$((#-1)):1}"

 echo "${@: -2:1}"

 echo "${@:~1:1}"