1 UNLOCKPT(3C)             Standard C Library Functions             UNLOCKPT(3C)
   2 
   3 NAME
   4        unlockpt - unlock a pseudo-terminal master/slave pair
   5 
   6 SYNOPSIS
   7        #include <stdlib.h>
   8 
   9        int unlockpt(int fildes);

  10 
  11 
  12 DESCRIPTION
  13        The unlockpt() function unlocks the slave pseudo-terminal device
  14        associated with the master to which fildes refers.



  15 


  16 
  17        Portable applications must call unlockpt() before opening the slave
  18        side of a pseudo-terminal device.
  19 
  20 RETURN VALUES
  21        Upon successful completion, unlockpt() returns 0. Otherwise, it returns
  22        -1 and sets errno to indicate the error.

  23 



  24 ERRORS
  25        The unlockpt() function may fail if:
  26 
  27        EBADF
  28                  The fildes argument is not a file descriptor open for
  29                  writing.
  30 


  31 
  32        EINVAL
  33                  The fildes argument is not associated with a master pseudo-
  34                  terminal device.
  35 


  36 
  37 ATTRIBUTES
  38        See attributes(5) for descriptions of the following attributes:
  39 
  40 
  41 
  42 
  43        +--------------------+-----------------+
  44        |  ATTRIBUTE TYPE    | ATTRIBUTE VALUE |
  45        +--------------------+-----------------+
  46        |Interface Stability | Standard        |
  47        +--------------------+-----------------+
  48        |MT-Level            | Safe            |
  49        +--------------------+-----------------+
  50 
  51 SEE ALSO
  52        open(2), grantpt(3C), ptsname(3C), attributes(5), standards(5)

  53 
  54 
  55        STREAMS Programming Guide
  56 
  57                                 August 14, 2002                   UNLOCKPT(3C)

   1 UNLOCKPT(3C)             Standard C Library Functions             UNLOCKPT(3C)
   2 
   3 NAME
   4      unlockpt - unlock a pseudo-terminal device pair
   5 
   6 SYNOPSIS
   7      #include <stdlib.h>
   8 
   9      int
  10      unlockpt(int fildes);
  11 

  12 DESCRIPTION
  13      When a pseudo-terminal manager device is opened, whether through
  14      posix_openpt(3C) or open(2) on a ptm(7D) device, the subsidiary device
  15      begins operation in a locked state.  The unlockpt() function unlocks the
  16      pseudo-terminal subsidiary device associated with the manager device to
  17      which fildes refers.
  18 
  19      Portable applications must call unlockpt() before opening the pseudo-
  20      terminal subsidiary device.
  21 



  22 RETURN VALUES
  23      The unlockpt() function returns the value 0 if successful; otherwise the
  24      value -1 is returned and the global variable errno is set to indicate the
  25      error.
  26 
  27 EXAMPLES
  28      See posix_openpt(3C) for an example that includes a call to unlockpt().
  29 
  30 ERRORS
  31      The unlockpt() function may fail if:
  32 
  33      EBADF              The fildes argument is not a file descriptor open for

  34                         writing.
  35 
  36      EINVAL             EINVAL The fildes argument is not associated with a
  37                         pseudo-terminal manager device.
  38 
  39 INTERFACE STABILITY
  40      Committed

  41 
  42 MT LEVEL
  43      Safe
  44 














  45 SEE ALSO
  46      open(2), grantpt(3C), posix_openpt(3C), ptsname(3C), attributes(5),
  47      standards(5), ptm(7D)
  48 
  49 illumos                        February 5, 2022                        illumos