Why are `/dev/ptmx` and `/dev/pts/ptmx` not device files?












0














On Lubuntu 18.04



$ file /dev/ptmx 

/dev/ptmx: character special (5/2)

$ file /dev/pts/ptmx 

/dev/pts/ptmx: character special (5/2)


What is the difference between /dev/ptmx and /dev/pts/ptmx?



https://unix.stackexchange.com/a/492304/674 says




On Linux, using devpts, there is no master device file. The process on the master end uses a file descriptor, which it gets by opening ptmx, but there’s no corresponding device node.




Did the author refer to /dev/ptmx or /dev/pts/ptmx?



Why are /dev/ptmx and /dev/pts/ptmx not device files? What types of files are they?



Thanks.






linux pseudoterminal






share



























    0














    On Lubuntu 18.04



    $ file /dev/ptmx 
    
/dev/ptmx: character special (5/2)
    
$ file /dev/pts/ptmx 
    
/dev/pts/ptmx: character special (5/2)


    What is the difference between /dev/ptmx and /dev/pts/ptmx?



    https://unix.stackexchange.com/a/492304/674 says




    On Linux, using devpts, there is no master device file. The process on the master end uses a file descriptor, which it gets by opening ptmx, but there’s no corresponding device node.




    Did the author refer to /dev/ptmx or /dev/pts/ptmx?



    Why are /dev/ptmx and /dev/pts/ptmx not device files? What types of files are they?



    Thanks.






    linux pseudoterminal






    share

























      0












      0








      0







      On Lubuntu 18.04



      $ file /dev/ptmx 
      
/dev/ptmx: character special (5/2)
      
$ file /dev/pts/ptmx 
      
/dev/pts/ptmx: character special (5/2)


      What is the difference between /dev/ptmx and /dev/pts/ptmx?



      https://unix.stackexchange.com/a/492304/674 says




      On Linux, using devpts, there is no master device file. The process on the master end uses a file descriptor, which it gets by opening ptmx, but there’s no corresponding device node.




      Did the author refer to /dev/ptmx or /dev/pts/ptmx?



      Why are /dev/ptmx and /dev/pts/ptmx not device files? What types of files are they?



      Thanks.






      linux pseudoterminal






      share













      On Lubuntu 18.04



      $ file /dev/ptmx 
      
/dev/ptmx: character special (5/2)
      
$ file /dev/pts/ptmx 
      
/dev/pts/ptmx: character special (5/2)


      What is the difference between /dev/ptmx and /dev/pts/ptmx?



      https://unix.stackexchange.com/a/492304/674 says




      On Linux, using devpts, there is no master device file. The process on the master end uses a file descriptor, which it gets by opening ptmx, but there’s no corresponding device node.




      Did the author refer to /dev/ptmx or /dev/pts/ptmx?



      Why are /dev/ptmx and /dev/pts/ptmx not device files? What types of files are they?



      Thanks.






      linux pseudoterminal




      linux pseudoterminal





      share












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      asked 2 mins ago









      Tim

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