insert a user defined variable in a command in bash












2















I would like to add an alias to a command in my .bashrc, as example:





alias take_row="cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'"


but I would like to specify the "nrow" variable when I launch the command from the terminal. As example:



take_row 1 --> the script take the first row



take_row 20 --> the script take the 20th row
etc



Does anybody knows hoe to write inside the command something like | etc






bash terminal variable bashrc assignment







share|improve this question





























    2















    I would like to add an alias to a command in my .bashrc, as example:




    
alias take_row="cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'"


    but I would like to specify the "nrow" variable when I launch the command from the terminal. As example:



    take_row 1 --> the script take the first row



    take_row 20 --> the script take the 20th row
    etc



    Does anybody knows hoe to write inside the command something like | etc






    bash terminal variable bashrc assignment







    share|improve this question



























      2












      2








      2








      I would like to add an alias to a command in my .bashrc, as example:




      
alias take_row="cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'"


      but I would like to specify the "nrow" variable when I launch the command from the terminal. As example:



      take_row 1 --> the script take the first row



      take_row 20 --> the script take the 20th row
      etc



      Does anybody knows hoe to write inside the command something like | etc






      bash terminal variable bashrc assignment







      share|improve this question
















      I would like to add an alias to a command in my .bashrc, as example:




      
alias take_row="cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'"


      but I would like to specify the "nrow" variable when I launch the command from the terminal. As example:



      take_row 1 --> the script take the first row



      take_row 20 --> the script take the 20th row
      etc



      Does anybody knows hoe to write inside the command something like | etc






      bash terminal variable bashrc assignment




      bash terminal variable bashrc assignment






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 29 mins ago









      Rui F Ribeiro

      39.6k1479132




      39.6k1479132










      asked 1 hour ago









      ccc.nrcccc.nrc

      163




      163






















          1 Answer
          1






          active

          oldest

          votes


















          3














          Use a function instead of an alias, in which case you can refer to positional parameters such as $1, etc.



          take_row () {
          
    local nrow=$1
          
    cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'
          
}


          In this particular case, you can also address the useless use of cat:



          take_row () {
          
    local nrow=$1
          
    awk -v nrow="${nrow}" '{if (NR==nrow) print}' prova.csv_001.txt
          
}





          share|improve this answer



















          • 1





            Thanks a lot for the suggestions!

            – ccc.nrc
            1 hour ago











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          1 Answer
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          active

          oldest

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          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          3














          Use a function instead of an alias, in which case you can refer to positional parameters such as $1, etc.



          take_row () {
          
    local nrow=$1
          
    cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'
          
}


          In this particular case, you can also address the useless use of cat:



          take_row () {
          
    local nrow=$1
          
    awk -v nrow="${nrow}" '{if (NR==nrow) print}' prova.csv_001.txt
          
}





          share|improve this answer



















          • 1





            Thanks a lot for the suggestions!

            – ccc.nrc
            1 hour ago
















          3














          Use a function instead of an alias, in which case you can refer to positional parameters such as $1, etc.



          take_row () {
          
    local nrow=$1
          
    cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'
          
}


          In this particular case, you can also address the useless use of cat:



          take_row () {
          
    local nrow=$1
          
    awk -v nrow="${nrow}" '{if (NR==nrow) print}' prova.csv_001.txt
          
}





          share|improve this answer



















          • 1





            Thanks a lot for the suggestions!

            – ccc.nrc
            1 hour ago














          3












          3








          3







          Use a function instead of an alias, in which case you can refer to positional parameters such as $1, etc.



          take_row () {
          
    local nrow=$1
          
    cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'
          
}


          In this particular case, you can also address the useless use of cat:



          take_row () {
          
    local nrow=$1
          
    awk -v nrow="${nrow}" '{if (NR==nrow) print}' prova.csv_001.txt
          
}





          share|improve this answer













          Use a function instead of an alias, in which case you can refer to positional parameters such as $1, etc.



          take_row () {
          
    local nrow=$1
          
    cat prova.csv_001.txt | awk -v nrow="${nrow}" '{if (NR==nrow) print}'
          
}


          In this particular case, you can also address the useless use of cat:



          take_row () {
          
    local nrow=$1
          
    awk -v nrow="${nrow}" '{if (NR==nrow) print}' prova.csv_001.txt
          
}






          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered 1 hour ago









          filbrandenfilbranden

          7,90021038




          7,90021038








          • 1





            Thanks a lot for the suggestions!

            – ccc.nrc
            1 hour ago














          • 1





            Thanks a lot for the suggestions!

            – ccc.nrc
            1 hour ago








          1




          1





          Thanks a lot for the suggestions!

          – ccc.nrc
          1 hour ago





          Thanks a lot for the suggestions!

          – ccc.nrc
          1 hour ago


















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