Alias with Variable in Bash

Alias with variable in bash

I'd create a function for that, rather than alias, and then exported it, like this:

function tail_ls { ls -l "$1" | tail; }

export -f tail_ls

Note -f switch to export: it tells it that you are exporting a function. Put this in your .bashrc and you are good to go.

Make a Bash alias that takes a parameter?

Bash alias does not directly accept parameters. You will have to create a function.

alias does not accept parameters but a function can be called just like an alias. For example:

myfunction() {
    #do things with parameters like $1 such as
    mv "$1" "$1.bak"
    cp "$2" "$1"
}


myfunction old.conf new.conf #calls `myfunction`

By the way, Bash functions defined in your .bashrc and other files are available as commands within your shell. So for instance you can call the earlier function like this

$ myfunction original.conf my.conf

Bash script add variable to alias

Forget the alias, and define a function.

ssh () {
    command ssh -2 -o StrictHostKeyChecking=no -o FallBackToRsh=no -q -i /root/.ssh/identity "$@"
}

bash resolve aliases and variables

$ cat defs
alias x='ls -al'; alias y='df -kh' # etc
xx='name'; yy='stuff'

$ cat diffsets
#!/bin/bash

# Restart with a clean environment in case the file has been sourced
# previously. We need the absolute path in the shebang above for this.
[[ -v HOME ]] && exec -c "$0" "$@"

# We must use full paths without variables in case those variables
# are also set in the file we're about to source.
[[ -s "$1" ]] &&
mkdir -p "/usr/tmp/diffsets_$$" &&
trap '
    rm -f "/usr/tmp/diffsets_$$/old" "/usr/tmp/diffsets_$$/new" &&
    rmdir "/usr/tmp/diffsets_$$"
' 0 &&

# We want to only compare variables, not function definitions, but we
# can't use `set -o posix` as we need newlines printed as $'\n' instead
# of literal newline chars for later comparison so ensure posix is disabled
# and use awk to exit when the first function is seen as they always are
# printed after variables.

set +o posix &&
set | awk '$NF=="()"{exit} 1' > "/usr/tmp/diffsets_$$/old" &&

. "$1" &&

set +o posix &&
set | awk '$NF=="()"{exit} 1' > "/usr/tmp/diffsets_$$/new" &&

comm -13 "/usr/tmp/diffsets_$$/old" "/usr/tmp/diffsets_$$/new"

$ ./diffsets defs
xx=name
yy=stuff

I'm specifically not using variables to hold the set output for comparison nor using mktemp to create the temp files (which would require variables to hold the mktemp output) as anything using variables in this script would fail if the file being sourced (defs in this case) contained a definition for those variables.

Bash alias containing a variable of the current directory

Make sure to use single quotes when defining the alias to prevent bash from expanding ${PWD} at definition time:

alias ooo='./manage.py --settings="${PWD##*/}.settings.dev"'

.bash_profile alias with variables

From man bash, under ALIASES:

There is no mechanism for using arguments in the replacement text. If arguments are needed, a shell function should be used (see FUNCTIONS below)."

Thus:

create() { touch "$1"; code "$1"; }

How do I pass a variable to a bash alias easier nmap scanning? (Function, alias, script…?)

It's just a function.

qmap() {
   nmap -sn "192.168.$1.1/24"
}

Reference variable in alias

Since you define your alias using double quotes, the $N is expanded before definition and your alias actually is echo 4.

Try this :

$N=4
$alias sayn='echo $N'
$N=2
$sayn
2

---

Related Topics