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unlockpt(3)
NAME
  unlockpt - Unlocks a pseudoterminal master and slave pair

LIBRARY
  Standard C Library (libc.so, libc.a)

SYNOPSIS
  #include <stdlib.h>

  int unlockpt(
	  int mastfd);

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  unlockpt():  XPG4-UNIX

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  mastfd    Specifies a file descriptor that is returned from a successful
	    open of the master pseudoterminal device.

DESCRIPTION
  The unlockpt() function unlocks a slave pseudoterminal from its associated
  master counterpart.  It does this by clearing a lock flag so that the slave
  device can be opened.

RETURN VALUE
  Upon successful completion, the unlockpt() function returns a value of 0.
  Otherwise, it returns a value of -1 and sets errno to indicate the error.

ERRORS
  The unlockpt() function sets errno to the specified values for the
  following conditions:

  [EBADF]
	 The file descriptor specified by the mastfd parameter is not an open
	 file descriptor.

  [EINVAL]
	 The file descriptor specified by the mastfd parameter is not
	 associated with a master pseudoterminal device.

RELATED INFORMATION
  Functions: openpty(3)


  Standards: standards(5)

  Guides: System V Compatibility User's Guide