Command_minishell_Correction

## BLOCCO 1 — SIMPLE COMMAND & GLOBAL 
- /bin/ls
- [Invio]
- [Spazi] + Invio
- [Tab] + Invio
- /bin/ls → echo $?
- /bin/nonexistent → echo $?
- exit 256 → echo $? 

## BLOCCO 2 — ARGUMENTS & HISTORY 
- /bin/ls -l
- /bin/echo hello world
- /usr/bin/env
- /bin/grep include minishell.h
- [Esegui comandi] → freccia ↑ ↓
- Ripeti comando da history → Invio

## BLOCCO 3 — ECHO 
- echo
- echo ciao mondo
- echo -n
- echo -nnnnn ciao
- echo ciao mondo -n
- echo "ciao mondo"
- echo "  con   spazi   "
- echo "$USER"
- echo '$USER'

## BLOCCO 4 — EXIT 
- exit
- exit 0
- exit 42
- exit 256 → echo $? 
- exit pippo → echo $?
- exit 10 pippo → echo $?

## BLOCCO 5 — RETURN VALUE OF A PROCESS
- /bin/ls → echo $?
- /bin/ls -l → echo $?
- /bin/echo hello > file.txt → echo $?
- /bin/nonexistent → echo $?
- /bin/ls filethatdoesntexist → echo $?
- /bin/false → expr $? + $?
- /bin/ls → /bin/nonexistent → expr $? + $?
- echo $(expr 2 + 3)

## BLOCCO 6 — SIGNALS 
- Ctrl-C a prompt vuoto
- Ctrl-\ a prompt vuoto
- Ctrl-D a prompt vuoto
- ls -l (non inviare) → Ctrl-C → Invio
- echo cia (non inviare) → Ctrl-D
- echo cia (non inviare) → Ctrl-\
- cat → Ctrl-C
- cat → Ctrl-\
- cat → Ctrl-D

## BLOCCO 7 — DOUBLE QUOTES 
- echo "Hello World"
- echo "This is a test"
- echo "This is a test with multiple words"
- echo "cat lol.c | cat > lol.c"
- export USER=Ilaria → echo "Hello $USER!"
- echo "Path: $PATH"
- echo "Test output" > output.txt → cat output.txt
- echo "cat file.txt | grep 'pattern' > output.txt"

## BLOCCO 8 — SINGLE QUOTES 
- echo '$USER'
- echo '$HOME'
- echo '$USER | grep test'
- echo '$USER > output.txt'
- echo '$USER | grep $USER > output.txt'
- echo ''
- echo 'Hello world, $USER'
- echo '$USER | echo "Test"'
- echo '$HOME/$USER'

## BLOCCO 9 — ENV 
- env
- export TEST_VAR=ciao → env | grep TEST_VAR
- export TEST_VAR=mondo → env | grep TEST_VAR
- export EMPTY_VAR= → env | grep EMPTY_VAR
- export SOLO_NOME → env | grep SOLO_NOME → export

## BLOCCO 10 — EXPORT 
- export MY_VAR=ciao → env | grep MY_VAR
- export MY_VAR=mondo → env | grep MY_VAR
- export EMPTY_VAR= → env | grep EMPTY_VAR
- export SOLO_NOME → env + export
- unset MY_VAR → env | grep MY_VAR
- export MY_VAR=nuovo_valore → env | grep MY_VAR
- export 1NOTVALID=ciao

## BLOCCO 11 — UNSET 
- export TEST_VAR=ciao → unset TEST_VAR → env | grep TEST_VAR
- export A=1 → export B=2 → unset A B → env | grep A/B
- unset XYZ
- unset 123ABC

## BLOCCO 12 — CD 
- cd /tmp → /bin/pwd
- cd .. → /bin/pwd
- cd . → /bin/pwd
- cd → /bin/pwd
- cd /this/path/does/not/exist
- cd dir1 dir2
- cd /tmp → echo $PWD

## BLOCCO 13 — PWD 
- pwd
- cd / → pwd
- cd /tmp → pwd
- cd .. → pwd
- pwd → pwd → pwd

## BLOCCO 14 — RELATIVE PATH 
- cd /bin → ./ls
- cd / → ./bin/ls
- cd /bin → ../bin/ls
- cd /usr/bin → ../../bin/ls
- cd /bin → ./nonexistent
- cd /; cd usr; cd ..; ./bin/ls

## BLOCCO 15 — ENVIRONMENT PATH 
- ls
- unset PATH → ls
- export PATH=/bin → ls
- export PATH=/tmp:/bin → ls (fake ls)
- export PATH=/bin:/tmp → ls
- export PATH=[default value]   -  export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin


## BLOCCO 16 — REDIRECTIONS

- echo "hello world" > test1.txt → cat test1.txt
- cat < test1.txt
- echo "second line" >> test1.txt → cat test1.txt
- cat < file1 < file2
- cat < test1.txt > test2.txt → cat test2.txt
- cat << EOF ... EOF
- grep hello << END ... END
- ls > out.txt → wc < out.txt
- cat < file_che_non_esiste.txt
- echo hello>file.txt → cat<file.txt

## BLOCCO 17 — PIPES

- cat file.txt | grep hello
- cat file.txt | grep hello | wc -l
- ls file_inesistente | grep bla | wc -l
- cat file.txt | grep hello > risultato.txt
- grep hello < file.txt | wc -l
- cat file.txt | grep hello >> out.txt
- < file.txt grep hello | wc -l
- cat file.txt | grep hello > nuovo.txt
- cat | grep hello → (Ctrl+D dopo input)
- < file.txt grep hello | sort | uniq > final.txt
- echo -e "ciao\nciao\nok" | uniq
- ls | comando_che_non_esiste | wc -l

## BLOCCO 18 — GO CRAZY & HISTORY

- ls -la (non invio) → Ctrl-C → Invio
- echo hello → pwd → ↑↓ navigation
- dsbksdgbksdghsd
- echo aaaa bbbb ... (molti argomenti)