64 lines
2.1 KiB
C
64 lines
2.1 KiB
C
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/****************************************************************************
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* libs/libc/unistd/lib_nice.c
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <sys/resource.h>
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#include <unistd.h>
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#include <errno.h>
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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/****************************************************************************
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* Name: nice
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*
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* Description:
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* The nice() function shall add the value of incr to the nice value of the
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* calling process. A process' nice value is a non-negative number for which
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* a more positive value shall result in less favorable scheduling.
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*
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****************************************************************************/
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int nice(int inc)
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{
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int prio;
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int ret;
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set_errno(0);
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ret = getpriority(PRIO_PROCESS, 0);
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if (get_errno() != 0)
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{
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return ret;
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}
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prio = ret + inc;
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ret = setpriority(PRIO_PROCESS, 0, prio);
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if (ret < 0)
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{
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return ret;
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}
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return prio;
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}
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