Ubuntu – How to pass answers to CLI script via arguments

command line

I'm writing a CLI script that asks a series of questions before doing a few things. How can I pass them as arguments so that I don't have to keep entering them every time I want to test my script?

Basically, it should pass 4 items to STDIN, like "text1[ENTER]text2[ENTER]text3[ENTER]text4[ENTER]" automatically.

Yes, I could modify my script to actually read the shell arguments, but I don't want to do it that way, since it's supposed to run more like a wizard.

Looking for something like

SOMEPROGRAM myscript arg1 arg2 arg3 arg4

SOMEPROGRAM arg1 arg2 arg3 arg4 | myscript

Or something like that. Is there such a program?

Best Answer

I understand you do not want to modify myscript.

Regarding the second solution you ask for, you can use printf:

printf '%s\n' text1 text2 text3 text4 | myscript

so that, defining an alias for SOMEPROGRAM as:

alias SOMEPROGRAM="printf '%s\n'"

you could effectively call

SOMEPROGRAM text1 text2 text3 text4 | myscript

The first form is ambiguous (from the point of view of SOMEPROGRAM), because it don't know where myscript options end and text parameters start, unless myscript is effectively invoked without any options. In this case you could use a function:

SOMEPROGRAM() {
  myscript="$1"
  shift
  printf '%s\n' "$@" | "$myscript"
}

so that you could effectively call

SOMEPROGRAM myscript text1 text2 text3 text4

Related Solutions

Ubuntu – Aliases – able to pass arguments

No, you can't pass arguments to an alias. But you can define a function:

compile() { 
  clang -ggdb -std=c99 -Wall -Werror ${1}.c -lcrypt -lcs50 -lm -o $1 ;
}

(you can put it all in one line if you wish, just mind the semicolon at the end of the command)

This will work as intended and is the recommended idiom that should replace aliases for all but trivial purposes.

But maybe what you really need is a Makefile?

Ubuntu – How to pass arguments to functions while executing a python script from terminal

You can also use the sys module. Here is an example :

import sys

first_arg = sys.argv[1]
second_arg = sys.argv[2]

def greetings(word1=first_arg, word2=second_arg):
    print("{} {}".format(word1, word2))

if __name__ == "__main__":
    greetings()
    greetings("Bonjour", "monde")

It has the behavior your are looking for :

$ python parse_args.py Hello world
Hello world
Bonjour monde

Best Answer

Related Solutions

Ubuntu – Aliases – able to pass arguments

Ubuntu – How to pass arguments to functions while executing a python script from terminal

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