What !! means while calling echo












0















Could somebody explain this output?



$ echo !

!

$ echo !!

echo echo !

echo !

$


I expected sedond echo to write only !!






command-line echo







share|improve this question























  • If you view your command history & decide you want to run command 419 in that history, you can type !419 and it'll execute. Provided answers tell you !! executes your last command, but it has other uses too :)

    – guiverc
    4 hours ago











  • Same question, although different context: askubuntu.com/q/627781/295286 Effectively duplicate

    – Sergiy Kolodyazhnyy
    3 hours ago











  • To prevent the !! from being evaluated (it's being evaluated prior to executing the echo cmd), use quotes, eg echo '!!' gnu.org/software/bash/manual/html_node/Quoting.html

    – michael
    3 hours ago
















0















Could somebody explain this output?



$ echo !

!

$ echo !!

echo echo !

echo !

$


I expected sedond echo to write only !!






command-line echo







share|improve this question























  • If you view your command history & decide you want to run command 419 in that history, you can type !419 and it'll execute. Provided answers tell you !! executes your last command, but it has other uses too :)

    – guiverc
    4 hours ago











  • Same question, although different context: askubuntu.com/q/627781/295286 Effectively duplicate

    – Sergiy Kolodyazhnyy
    3 hours ago











  • To prevent the !! from being evaluated (it's being evaluated prior to executing the echo cmd), use quotes, eg echo '!!' gnu.org/software/bash/manual/html_node/Quoting.html

    – michael
    3 hours ago














0












0








0








Could somebody explain this output?



$ echo !

!

$ echo !!

echo echo !

echo !

$


I expected sedond echo to write only !!






command-line echo







share|improve this question














Could somebody explain this output?



$ echo !

!

$ echo !!

echo echo !

echo !

$


I expected sedond echo to write only !!






command-line echo




command-line echo






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 4 hours ago









SanyaSanya

12




12













  • If you view your command history & decide you want to run command 419 in that history, you can type !419 and it'll execute. Provided answers tell you !! executes your last command, but it has other uses too :)

    – guiverc
    4 hours ago











  • Same question, although different context: askubuntu.com/q/627781/295286 Effectively duplicate

    – Sergiy Kolodyazhnyy
    3 hours ago











  • To prevent the !! from being evaluated (it's being evaluated prior to executing the echo cmd), use quotes, eg echo '!!' gnu.org/software/bash/manual/html_node/Quoting.html

    – michael
    3 hours ago



















  • If you view your command history & decide you want to run command 419 in that history, you can type !419 and it'll execute. Provided answers tell you !! executes your last command, but it has other uses too :)

    – guiverc
    4 hours ago











  • Same question, although different context: askubuntu.com/q/627781/295286 Effectively duplicate

    – Sergiy Kolodyazhnyy
    3 hours ago











  • To prevent the !! from being evaluated (it's being evaluated prior to executing the echo cmd), use quotes, eg echo '!!' gnu.org/software/bash/manual/html_node/Quoting.html

    – michael
    3 hours ago

















If you view your command history & decide you want to run command 419 in that history, you can type !419 and it'll execute. Provided answers tell you !! executes your last command, but it has other uses too :)

– guiverc
4 hours ago





If you view your command history & decide you want to run command 419 in that history, you can type !419 and it'll execute. Provided answers tell you !! executes your last command, but it has other uses too :)

– guiverc
4 hours ago













Same question, although different context: askubuntu.com/q/627781/295286 Effectively duplicate

– Sergiy Kolodyazhnyy
3 hours ago





Same question, although different context: askubuntu.com/q/627781/295286 Effectively duplicate

– Sergiy Kolodyazhnyy
3 hours ago













To prevent the !! from being evaluated (it's being evaluated prior to executing the echo cmd), use quotes, eg echo '!!' gnu.org/software/bash/manual/html_node/Quoting.html

– michael
3 hours ago





To prevent the !! from being evaluated (it's being evaluated prior to executing the echo cmd), use quotes, eg echo '!!' gnu.org/software/bash/manual/html_node/Quoting.html

– michael
3 hours ago










2 Answers
2






active

oldest

votes


















1














!! means last command.



echo !! will echo last command, which was echo !.






share|improve this answer































    0














    Easily explained:



    $ echo 1
    
1
    
$ !!
    
echo 1
    
1


    so !! just repeats the last command, so



    echo !!


    does excactly what it's supposed to to!



    ;-)






    share|improve this answer

























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      2 Answers
      2






      active

      oldest

      votes








      2 Answers
      2






      active

      oldest

      votes









      active

      oldest

      votes






      active

      oldest

      votes









      1














      !! means last command.



      echo !! will echo last command, which was echo !.






      share|improve this answer




























        1














        !! means last command.



        echo !! will echo last command, which was echo !.






        share|improve this answer


























          1












          1








          1







          !! means last command.



          echo !! will echo last command, which was echo !.






          share|improve this answer













          !! means last command.



          echo !! will echo last command, which was echo !.







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered 4 hours ago









          Manoj SawaiManoj Sawai

          6641720




          6641720

























              0














              Easily explained:



              $ echo 1
              
1
              
$ !!
              
echo 1
              
1


              so !! just repeats the last command, so



              echo !!


              does excactly what it's supposed to to!



              ;-)






              share|improve this answer






























                0














                Easily explained:



                $ echo 1
                
1
                
$ !!
                
echo 1
                
1


                so !! just repeats the last command, so



                echo !!


                does excactly what it's supposed to to!



                ;-)






                share|improve this answer




























                  0












                  0








                  0







                  Easily explained:



                  $ echo 1
                  
1
                  
$ !!
                  
echo 1
                  
1


                  so !! just repeats the last command, so



                  echo !!


                  does excactly what it's supposed to to!



                  ;-)






                  share|improve this answer















                  Easily explained:



                  $ echo 1
                  
1
                  
$ !!
                  
echo 1
                  
1


                  so !! just repeats the last command, so



                  echo !!


                  does excactly what it's supposed to to!



                  ;-)







                  share|improve this answer














                  share|improve this answer



                  share|improve this answer








                  edited 3 hours ago









                  wjandrea

                  9,22442463




                  9,22442463










                  answered 4 hours ago









                  FabbyFabby

                  26.8k1360161




                  26.8k1360161






























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