Krdytkyu

Aliases are deprecated in favor of shell functions. From the bash manual page:

For almost every purpose, aliases are superseded by shell functions.

To create a function, and export it to subshells, put the following in your ~/.bashrc:

petsc() {

    ~/petsc-3.2-p6/petsc-arch/bin/mpiexec "$@"

}

export -f petsc

Then you can freely call your command from your scripts.

Shell functions and aliases are limited to the shell and do not work in executed shell scripts. Alternatives for your case:

• 
  

  (if you do not bother to use mpiexec instead of petsc) Add $HOME/petsc-3.2-p6/petsc-arch/bin to your PATH variable. This can be done by editing ~/.profile and appending:

  
  
  

  PATH="$HOME/petsc-3.2-p6/petsc-arch/bin:$PATH"
  
  

  
  
  

  Re-login to apply these changes

  
  


• 
  

  Create the directory ~/bin and

  
  
  
  
  
  • 
    

    make a wrapper script named petsc containing:

    
    
    

    #!/bin/sh
    
    exec ~/petsc-3.2-p6/petsc-arch/bin/mpiexec "$@"
    
    

    
    
  
  
  • 
    

    if the program allows for it, you can skip the shellscript and make a symlink using the command:

    
    
    

    ln -s ~/petsc-3.2-p6/petsc-arch/bin/mpiexec ~/bin/petsc
    
    

    
    
  
  
  
  

In bash 4 you can use special variable: $BASH_ALIASES.

For example:

$ alias foo="echo test"

$ echo ${BASH_ALIASES[foo]}

echo test

$ echo `${BASH_ALIASES[foo]}` bar

test bar

Alternatively define as variable then use command substitution or eval.

So for example, instead of defining the alias such as:

alias foo="echo test"

define it as:

foo="echo test"

instead. Then execute it by either:

find . -type f -exec sh -c "eval $foo" ;

or:

find . -type f -exec sh -c "echo `$foo`" ;

1. 
   

   In .bash_aliases:

   
   
   

   petsc {
   
   ~/petsc-3.2-p6/petsc-arch/bin/mpiexec "$@"
   
   }
   
   

   
   
   

   Or put the function in .bashrc. Usually in .bashrc only config settings of bash are stored.

   
   



2. In Terminal: source .bash_aliases



3. Call it: petsc arg(s)
   

Advantage: you do not need export -f petscin .bash_aliases. Aliases are deprecated but using .bash_aliases for functions is ok.

You can force bash to execute your script as an interactive shell with the -i flag. This will tell your .bashrc file to define aliases and other functions.

Example:

~ $ grep ll .bashrc

alias ll='ls -lah'

~ $ cat script.sh 

#!/bin/sh



ll

~ $ bash script.sh 

script.sh: line 3: ll: command not found

~ $ bash -i script.sh

..directory contents..

More info:

$ man bash

1. Use your aliases in your shell script.


2. Source your script in your current, interactive shell instead of executing it.

So if you have a file called script.sh with your commands that include using aliases, simply type:

source script.sh

ALIASES

   ...

   Aliases are not expanded when the shell is not interactive, unless the expand_aliases shell option is set using shopt (see the description of shopt under SHELL BUILTIN COMMANDS

   below).

So the real answer to this question, for those looking to use actual aliases in shell scripts instead of alternatives to them, is:

#!/bin/bash



shopt -s expand_aliases



alias foo=bar



foo whatever

As for why I'd want to do this: Due to unusual circumstances, I need to trick a Dockerfile into thinking it's a shell script.

(EDIT: removed functions since I misread calling of mpiexec.)

If the only thing you need is less typing, why don't you just put the folder in $PATH? Or make a symlink to mpiexec from some folder in $PATH? Or (my favourite) put the alias in a script that you source in the calling script?