How does xargs know when a stdin input ends, so that it can start processing it?











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After reading Stephen Kitt's reply, xargs waits for receiving the stdin input before processing any of the input, such as splitting it into arguments.



How does xargs know when a stdin input ends, so that it can start processing it?



Is -E used for specifying the end of a stdin input?



Without it, how does xargs knows when it ends? Is there some timeout?






xargs







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    up vote
    3
    down vote

    favorite
    1












    After reading Stephen Kitt's reply, xargs waits for receiving the stdin input before processing any of the input, such as splitting it into arguments.



    How does xargs know when a stdin input ends, so that it can start processing it?



    Is -E used for specifying the end of a stdin input?



    Without it, how does xargs knows when it ends? Is there some timeout?






    xargs







    share|improve this question







    New contributor




    Ben is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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      up vote
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      down vote

      favorite
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      up vote
      3
      down vote

      favorite
      1






      1





      After reading Stephen Kitt's reply, xargs waits for receiving the stdin input before processing any of the input, such as splitting it into arguments.



      How does xargs know when a stdin input ends, so that it can start processing it?



      Is -E used for specifying the end of a stdin input?



      Without it, how does xargs knows when it ends? Is there some timeout?






      xargs







      share|improve this question







      New contributor




      Ben is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      After reading Stephen Kitt's reply, xargs waits for receiving the stdin input before processing any of the input, such as splitting it into arguments.



      How does xargs know when a stdin input ends, so that it can start processing it?



      Is -E used for specifying the end of a stdin input?



      Without it, how does xargs knows when it ends? Is there some timeout?






      xargs




      xargs






      share|improve this question







      New contributor




      Ben is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      share|improve this question







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      Ben is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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          In the absence of an -E option, which specifies an explicit end-of-file marker, xargs knows it’s exhausted its standard input (or any input specified by the -a option) when read() returns 0.



          You can see this in action by running



          printf '%s ' {1..1024} | strace -e read xargs -s 2048 -x





          share|improve this answer























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            up vote
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            In the absence of an -E option, which specifies an explicit end-of-file marker, xargs knows it’s exhausted its standard input (or any input specified by the -a option) when read() returns 0.



            You can see this in action by running



            printf '%s ' {1..1024} | strace -e read xargs -s 2048 -x





            share|improve this answer



























              up vote
              6
              down vote













              In the absence of an -E option, which specifies an explicit end-of-file marker, xargs knows it’s exhausted its standard input (or any input specified by the -a option) when read() returns 0.



              You can see this in action by running



              printf '%s ' {1..1024} | strace -e read xargs -s 2048 -x





              share|improve this answer

























                up vote
                6
                down vote










                up vote
                6
                down vote









                In the absence of an -E option, which specifies an explicit end-of-file marker, xargs knows it’s exhausted its standard input (or any input specified by the -a option) when read() returns 0.



                You can see this in action by running



                printf '%s ' {1..1024} | strace -e read xargs -s 2048 -x





                share|improve this answer














                In the absence of an -E option, which specifies an explicit end-of-file marker, xargs knows it’s exhausted its standard input (or any input specified by the -a option) when read() returns 0.



                You can see this in action by running



                printf '%s ' {1..1024} | strace -e read xargs -s 2048 -x






                share|improve this answer














                share|improve this answer



                share|improve this answer








                edited 1 hour ago

























                answered 1 hour ago









                Stephen Kitt

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