Why does my script return a syntax error?

Question

I wrote this script, but I don't know why I have a syntax error:

#!/bin/bash
    echo Indica la fecha de hoy en formato dd-mm-aaaa
    read date
    echo Indica la hora actual en formato hh-mm
    read hora
    mkdir -p /re/plugins
    shopt -s extglob
    cp -R /files/spigot/plugins/!(dynmap) /re/plugins
    shopt -u extglob
    cp -R /files/spigot/world /re
    zip -r "$date"-"$hora".zip plugins world
    mv /re/*.zip /var/www/html/backup
    rm -R /re
    Echo copia de seguridad realizada correctamente el dia "$date" a las "$hora"h > /log.txt

The output

root@alex:/home/alex# sh pb.sh
Indica la fecha de hoy en formato dd-mm-aaaa
aaa
Indica la hora actual en formato hh-mm
sdf
pb.sh: 7: pb.sh: shopt: not found
pb.sh: 8: pb.sh: Syntax error: "(" unexpected
root@alex:/home/alex# 

Answer 1

Your problem is right here:

root@alex:/home/alex# sh pb.sh  

shopt is a shell builtin (see type shopt). /bin/sh isn't bash on Ubuntu, but a compatibility shell called dash. Dash doesn't have shopt.

Since the first line of your script is the shebang line (#!/bin/bash) you can just run your script like this:

./pb.sh  

and it should work fine. You may need to set the file as executable by running:

chmod +x pb.sh

Answer 2

pb.sh: 8: pb.sh: Syntax error: "(" unexpected

The !(dynmap) syntax is only recognized when the extglob shell option has been set, and it hadn't:

pb.sh: 7: pb.sh: shopt: not found

The shopt command wasn't found because it's a shell builtin and the particular shell that ran the script doesn't support it, as Seth's answer explains.