pid_block, pid_unblock - stops (blocks) or resumes (unblocks) the specified process
#include <types.h> #include <sys/time.h>
struct timeval *tp,
Standard C Library (libc)
Specifies the timeout value for the blocked process. If tp is NULL, the process sleeps until either it receives a signal or it is unblocked by a pid_unblock. Specifies the process ID of the process to unblock. Specifies flags that can be passed to the pid_block() and pid_unblock() functions.
The pid_block() function blocks execution of the process until one of the following conditions occurs: The process is unblocked by the pid_unblock() function. A signal is sent to the process. The optional timeout period expires.
The pid_unblock function forces the specified process, previously suspended via a call to pid_block, to be made runnable.
Unless you are operating with superuser authority,
can affect only processes that you own. When operating with superuser
authority, you can unblock any process.
functions are not portable. The behavior of these functions when called from
a multithreaded application is nondeterministic.
Upon successful completion, the
functions return a value of
Otherwise, they return a value of
to indicate the error:
parameter specified an invalid
parameter specified a time that
was too large to be handled, or the
function was not found.
The real or saved user ID does not match the real or effective
user ID of the target process or the calling process does not have appropriate
A signal interrupted the suspended process.
System call timed out.