linux c++ 得到指定进程名线程数-蒲公英云

linux c++ 得到指定进程名线程数

悠悠 2021-09-02 08:03 1081阅读 0赞

代码如下：

#include<iostream>
#include<stdlib.h>
#include<stdio.h>
#include<string.h>
using namespace std;
int getProcessIdByExeName(const char* pName)
{
    char buf[256] = {0};
    snprintf(buf,sizeof(buf),"ps -ef | grep \"%s\" | grep -v grep | awk '{print $2}'",pName);
    FILE* fp = popen(buf,"r");
    if(fp == NULL)
    {
        printf("popen failed, buf = %s",buf);
        return -1;
    }
    char oBuf[256] = {0};
    fgets(oBuf,256,fp);
    if(strlen(oBuf) == 0)
    {
        pclose(fp);
        return -1;
    }
    oBuf[strlen(oBuf)-1] = '\0';
    pclose(fp);
    return atoi(oBuf);
}
int getThread(const std::string& strSrvName)
{
    int iPid = -1;
    iPid = getProcessIdByExeName(strSrvName.c_str());
    if(iPid < 0)
    {
        printf("get pid faild [%s]",strSrvName.c_str());
        return -1;
    }
    char szFileName[64] = {0};
    FILE* fd =NULL;
    char szLineBuff[512] = { 0 };
    sprintf(szFileName, "/proc/%ld/status", iPid);
    fd = fopen(szFileName, "r");
    if(fd == NULL)
    {
        printf("open file %s failed",szFileName);
        return -1;
    }
    int iThread = -1;
    while (fgets(szLineBuff, sizeof(szLineBuff), fd) != NULL)
    {
        char szName[64] = {0};
        int iValue = 0;
        sscanf(szLineBuff, "%s", szName);//%s遇空格停止
        // 进程使用的线程数
        if (strcmp(szName, "Threads:") == 0)
        {
            sscanf(szLineBuff, "%s %d", szName, &iValue);
            iThread = iValue;
            break;
        }
    }
    fclose(fd);
    return iThread;
}
int main()
{
    int ret=getThread("alarm");
    printf("alarm exe's threads =%d\n",ret);
    return 0;
}