January 20, 2007 _LWP_UNPARK 2

### NAME

_lwp_unpark - resume execution of a waiting LWP

### LIBRARY

Standard C Library (libc, -lc)

### SYNOPSIS

```int` _lwp_unpark(```lwpid_t lwp``, const void *hint`)

### DESCRIPTION

_lwp_unpark(``) resumes execution of the light-weight process ```lwp`.

The target LWP is assumed to be waiting in the kernel as a result of a call to _lwp_park(``). If the target LWP is not currently waiting, it will return immediatley upon the next call to _lwp_park(``).

See _lwp_park(2) for a description of the ```hint` argument.

### RETURN VALUES

A 0 value indicates that the call succeeded. A -1 return value indicates an error occurred and errno is set to indicate the reason.

### ERRORS

[```ESRCH`]
  No LWP can be found in the current process corresponding to that specified by ```lwp`.

### SEE ALSO

_lwp_park(2), _lwp_unpark_all(2), _lwp_wakeup(2)

### HISTORY

The _lwp_unpark(``) system call first appeared in NetBSD5.0.