Изменить приоритет процесса
#include <unistd.h>int nice( int incr );
libc
The nice() function allows a process to change its priority. The invoking process must be in a scheduling class that supports the operation.
![]() | This function has no effect in any of the scheduling policies that ЗОСРВ «Нейтрино» supports. Use sched_setparam(), pthread_setschedparam(), or pthread_setschedprio() instead of this function. |
The nice() function adds the value of incr to the nice value of the calling process. A process's nice value is a nonnegative number; a greater positive value results in a lower CPU priority.
A maximum nice value of 2
* NZERO
- 1
and a minimum nice value of 0
are imposed by the system. NZERO
is defined in <limits.h>
with a default value of 20
. If you request a value above or below these limits, the nice value is set to the corresponding limit. A nice value of 40
is treated as 39
. Only a process with superuser privileges can lower the nice value.
Новое nice-значение минус NZERO
. Если возникла ошибка функция возвращает -1
, приоритет потока не меняется, код ошибки записывается в errno.
40
, and the effective user ID of the calling process isn't the superuser. POSIX 1003.1 XSI
As -1
is a permissible return value in a successful situation, an application wishing to check for error situations should set errno to 0
, then call nice(), and if it returns -1
, check to see if errno is nonzero.
execl(), execle(), execlp(), execlpe(), execv(), execve(), execvp(), execvpe(), pthread_setschedparam(), pthread_setschedprio(), sched_setparam()
nice в Справочнике по Утилитам
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