Doubt with exercise in Shellscript

Question

I would like some help to resolve these exercises:

In the Ex4.1.sh script add the option to enter the word and file name directly from the command line this way:

$  ./ex4.1.sh  <palavra>  <arquivo> 

In the Ex4.1.sh script the result of the "grep" command is shown on the screen. Change the script in such a way that this result does not appear on the screen. Write a script that tests whether the value passed as a day, month and year parameter is a valid date.

The script in the case is this one:

#!/bin/bash
# ex4.1.sh - teste de desvio
# Script para verificacao de estrutura de desvio
# localiza uma string em um arquivo
echo -n "Digite a palavra a ser localizada: "
read palavra
echo -n "Qual o arquivo a procurar?: "
read arquivo
if grep $palavra $arquivo
 then
   echo "$palavra encontrada no arquivo $arquivo"
   sleep 5
 else
   echo "$palavra não encontrada no arquivo $arquivo"
   sleep 5
 fi

Hello fedorqui colleague I managed to solve this example you gave, the problem is I was making it as a script with the code typed in gedit when it was to type directly in the command prompt of linux, there is the result

$ date -d "holaaa" 2> /dev/null && echo "Correct" || echo "Incorrect"

Incorrect

$ date -d "06 Dec 2017" 2> /dev/null && echo "Correct" || echo "Incorrect"

Wednesday Dec 6 00:00:00 AMT 2017

Correct

Answer 1

In the Ex4.1.sh script add the option to enter the word and file name directly from the command line this way:

Picks up values with $1, $2...:

palavra=$1
arquivo=$2

Thus, $palavra contains the first and $arquivo the second:

With script.sh:

#!/bin/bash

palavra=$1
arquivo=$2
echo "palavra: $palavra. arquivo: $arquivo"

I’m gonna run:

$ ./script.sh "uma palavra" "hola.txt"
palavra: uma palavra. arquivo: hola.txt

---

Change the script in such a way that this result does not appear on the screen

Takes the results in a variable:

res=$(grep "$palavra" "$arquivo")

---

Write a script that tests whether the value passed as a day, month and year parameter is a valid date.

Usa date -d"<fecha>":

$ date -d"holaaa" && echo "correcto" || echo "incorreto"
date: invalid date ‘holaaa’
incorreto
$ date -d"23 Mar 2017" && echo "correcto" || echo "incorreto"
Thu Mar 23 00:00:00 CET 2017
correcto