阅读Darwin源码的时候看到这个方法,感觉挺有用处,且考虑了多种平台下的实现方式,直接贴代码,以后说不定会用到~
单一种平台下的实现方法可能很容易,但是把这些个系统都收集在一起,在一个函数中实现还是极好的
UInt32 OS::GetNumProcessors() { #if (__Win32__) SYSTEM_INFO theSystemInfo; ::GetSystemInfo(&theSystemInfo); return (UInt32)theSystemInfo.dwNumberOfProcessors; #endif #if (__MacOSX__ || __FreeBSD__) int numCPUs = 1; size_t len = sizeof(numCPUs); int mib[2]; mib[0] = CTL_HW; mib[1] = HW_NCPU; (void) ::sysctl(mib,2,&numCPUs,&len,NULL,0); if (numCPUs < 1) numCPUs = 1; return (UInt32) numCPUs; #endif #if(__linux__ || __linuxppc__) char cpuBuffer[8192] = ""; StrPtrLen cpuInfoBuf(cpuBuffer, sizeof(cpuBuffer)); FILE *cpuFile = ::fopen( "/proc/cpuinfo", "r" ); if (cpuFile) { cpuInfoBuf.Len = ::fread(cpuInfoBuf.Ptr, sizeof(char), cpuInfoBuf.Len, cpuFile); ::fclose(cpuFile); } StringParser cpuInfoFileParser(&cpuInfoBuf); StrPtrLen line; StrPtrLen word; UInt32 numCPUs = 0; while( cpuInfoFileParser.GetDataRemaining() != 0 ) { cpuInfoFileParser.GetThruEOL(&line); // Read each line StringParser lineParser(&line); lineParser.ConsumeWhitespace(); //skip over leading whitespace if (lineParser.GetDataRemaining() == 0) // must be an empty line continue; lineParser.ConsumeUntilWhitespace(&word); if ( word.Equal("processor") ) // found a processor as first word in line { numCPUs ++; } } if (numCPUs == 0) numCPUs = 1; return numCPUs; #endif #if(__solaris__) { UInt32 numCPUs = 0; char linebuff[512] = ""; StrPtrLen line(linebuff, sizeof(linebuff)); StrPtrLen word; FILE *p = ::popen("uname -X","r"); while((::fgets(linebuff, sizeof(linebuff -1), p)) > 0) { StringParser lineParser(&line); lineParser.ConsumeWhitespace(); //skip over leading whitespace if (lineParser.GetDataRemaining() == 0) // must be an empty line continue; lineParser.ConsumeUntilWhitespace(&word); if ( word.Equal("NumCPU")) // found a tag as first word in line { lineParser.GetThru(NULL,'='); lineParser.ConsumeWhitespace(); //skip over leading whitespace lineParser.ConsumeUntilWhitespace(&word); //read the number of cpus if (word.Len > 0) ::sscanf(word.Ptr, "%"_U32BITARG_"", &numCPUs); break; } } if (numCPUs == 0) numCPUs = 1; ::pclose(p); return numCPUs; } #endif #if(__sgi__) UInt32 numCPUs = 0; numCPUs = sysconf(_SC_NPROC_ONLN); return numCPUs; #endif return 1; }
PS: 函数摘自Darwin源码:\StreamServer\CommonUtilitiesLib\OS.cpp
时间: 2024-11-09 10:15:31