How do I check if a file exists by trimming a given string?












0















Lets say I have the following files Foo-Bar1.mp3 Foo-Bar2.jpg Foo-Bar1.mp3 Foo-Bar1.mp4
I want to download them so they are in a url like www.example.com/1/Foo%20-Bar1.mp3
I want to cut the URL so that I can use it to check if the file exists before I download it



if [ ! -f Foo-Bar1.mp3 ]; then

#Download it

fi`





bash terminal







share|improve this question



























    0















    Lets say I have the following files Foo-Bar1.mp3 Foo-Bar2.jpg Foo-Bar1.mp3 Foo-Bar1.mp4
    I want to download them so they are in a url like www.example.com/1/Foo%20-Bar1.mp3
    I want to cut the URL so that I can use it to check if the file exists before I download it



    if [ ! -f Foo-Bar1.mp3 ]; then
    
#Download it
    
fi`





    bash terminal







    share|improve this question

























      0












      0








      0








      Lets say I have the following files Foo-Bar1.mp3 Foo-Bar2.jpg Foo-Bar1.mp3 Foo-Bar1.mp4
      I want to download them so they are in a url like www.example.com/1/Foo%20-Bar1.mp3
      I want to cut the URL so that I can use it to check if the file exists before I download it



      if [ ! -f Foo-Bar1.mp3 ]; then
      
#Download it
      
fi`





      bash terminal







      share|improve this question














      Lets say I have the following files Foo-Bar1.mp3 Foo-Bar2.jpg Foo-Bar1.mp3 Foo-Bar1.mp4
      I want to download them so they are in a url like www.example.com/1/Foo%20-Bar1.mp3
      I want to cut the URL so that I can use it to check if the file exists before I download it



      if [ ! -f Foo-Bar1.mp3 ]; then
      
#Download it
      
fi`





      bash terminal




      bash terminal






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 22 '18 at 15:40









      Bret JosephBret Joseph

      8410




      8410
























          1 Answer
          1






          active

          oldest

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          2














          You can use parameter expansion to accomplish this :



           $ url='www.example.com/1/Foo%20-Bar1.mp3'
          
 $ name=${url##*/}
          
 $ echo $name
          
    Foo%20-Bar1.mp3
          
 $ echo ${name/%20/}
          
     Foo-Bar1.mp3


          Regards!



          Note - As noted by @oguzismail you can use echo -e ${name//%/x} to decode each url character.






          share|improve this answer





















          • 3





            You can use echo -e ${name//%/\x} to decode every % encoded char.

            – oguzismail
            Nov 22 '18 at 15:57








          • 1





            Nice! Thanks for the tip. Im adding your contribution.

            – Matias Barrios
            Nov 22 '18 at 16:00











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          1 Answer
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          1 Answer
          1






          active

          oldest

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          active

          oldest

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          active

          oldest

          votes









          2














          You can use parameter expansion to accomplish this :



           $ url='www.example.com/1/Foo%20-Bar1.mp3'
          
 $ name=${url##*/}
          
 $ echo $name
          
    Foo%20-Bar1.mp3
          
 $ echo ${name/%20/}
          
     Foo-Bar1.mp3


          Regards!



          Note - As noted by @oguzismail you can use echo -e ${name//%/x} to decode each url character.






          share|improve this answer





















          • 3





            You can use echo -e ${name//%/\x} to decode every % encoded char.

            – oguzismail
            Nov 22 '18 at 15:57








          • 1





            Nice! Thanks for the tip. Im adding your contribution.

            – Matias Barrios
            Nov 22 '18 at 16:00
















          2














          You can use parameter expansion to accomplish this :



           $ url='www.example.com/1/Foo%20-Bar1.mp3'
          
 $ name=${url##*/}
          
 $ echo $name
          
    Foo%20-Bar1.mp3
          
 $ echo ${name/%20/}
          
     Foo-Bar1.mp3


          Regards!



          Note - As noted by @oguzismail you can use echo -e ${name//%/x} to decode each url character.






          share|improve this answer





















          • 3





            You can use echo -e ${name//%/\x} to decode every % encoded char.

            – oguzismail
            Nov 22 '18 at 15:57








          • 1





            Nice! Thanks for the tip. Im adding your contribution.

            – Matias Barrios
            Nov 22 '18 at 16:00














          2












          2








          2







          You can use parameter expansion to accomplish this :



           $ url='www.example.com/1/Foo%20-Bar1.mp3'
          
 $ name=${url##*/}
          
 $ echo $name
          
    Foo%20-Bar1.mp3
          
 $ echo ${name/%20/}
          
     Foo-Bar1.mp3


          Regards!



          Note - As noted by @oguzismail you can use echo -e ${name//%/x} to decode each url character.






          share|improve this answer















          You can use parameter expansion to accomplish this :



           $ url='www.example.com/1/Foo%20-Bar1.mp3'
          
 $ name=${url##*/}
          
 $ echo $name
          
    Foo%20-Bar1.mp3
          
 $ echo ${name/%20/}
          
     Foo-Bar1.mp3


          Regards!



          Note - As noted by @oguzismail you can use echo -e ${name//%/x} to decode each url character.







          share|improve this answer














          share|improve this answer



          share|improve this answer








          edited Nov 22 '18 at 16:01

























          answered Nov 22 '18 at 15:54









          Matias BarriosMatias Barrios

          1,547317




          1,547317








          • 3





            You can use echo -e ${name//%/\x} to decode every % encoded char.

            – oguzismail
            Nov 22 '18 at 15:57








          • 1





            Nice! Thanks for the tip. Im adding your contribution.

            – Matias Barrios
            Nov 22 '18 at 16:00














          • 3





            You can use echo -e ${name//%/\x} to decode every % encoded char.

            – oguzismail
            Nov 22 '18 at 15:57








          • 1





            Nice! Thanks for the tip. Im adding your contribution.

            – Matias Barrios
            Nov 22 '18 at 16:00








          3




          3





          You can use echo -e ${name//%/\x} to decode every % encoded char.

          – oguzismail
          Nov 22 '18 at 15:57







          You can use echo -e ${name//%/\x} to decode every % encoded char.

          – oguzismail
          Nov 22 '18 at 15:57






          1




          1





          Nice! Thanks for the tip. Im adding your contribution.

          – Matias Barrios
          Nov 22 '18 at 16:00





          Nice! Thanks for the tip. Im adding your contribution.

          – Matias Barrios
          Nov 22 '18 at 16:00




















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