/* pidfind_tch */

#include <dirent.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

long int get_pid_by_process_name(char *pname)
{
	DIR *d;
	struct dirent *dir;
	FILE *f;
	char entry[24];
	char buf[256];
	long int l;

	d = opendir("/proc");
	if (d)
	{
		while ((dir = readdir(d)) != NULL)
		{
			strcpy(entry, "/proc/");
			strcat(entry, dir->d_name);
			strcat(entry, "/cmdline");
			f = fopen(entry, "rb");
			if (f != NULL)
			{
				fread(&buf[0], 1, 256, f);
				fclose(f);
				l = -1;
				while ((++l < 257) && (buf[l]) && (buf[l] != 32));
				buf[l] -= (buf[l] == 32) << 5;
				if (l)
				{
					while ((buf[--l] != 47) && l);
					l += (buf[l] == 47);
					if (!strcmp(pname, &buf[l]))
					{
						return atol(dir->d_name);
					}
				}
			}
		}
		return -1; /* nincs ilyen */
		closedir(d);
	}
	return -2; /* nem lehet megnyitni a /proc-ot */
}


int main(int argc, char *argv[])
{
	/*QCoreApplication a(argc, argv);*/

	int i;

	for (i = 0; i < 1000; ++i)
	{
		get_pid_by_process_name("konsole");
		get_pid_by_process_name("opera");
		get_pid_by_process_name("d3lphin");
		get_pid_by_process_name("mousepad");
	}

	return 0;
}

/* pidfind_kemi */

#include <QCoreApplication>
#include <QProcess>
#include <QStringList>
#include <stdio.h>

int getPID(QString processName)
{
	QProcess proc;
	QStringList args;
	args << "-c" << "ps aux | grep \"" + processName + "\" | grep \"root\"";
	proc.start("/bin/sh", args);
	proc.waitForFinished();
	QString s = proc.readLine();
	QStringList list = s.simplified().split(" ");
	if (list[0] != "root")
	{
		return -1;
	}
	return list[1].toInt();
}

int main(int argc, char *argv[])
{
	/*QCoreApplication a(argc, argv);*/

	int i;

	for (i = 0; i < 1000; ++i)
	{
		getPID("konsole");
		getPID("opera");
		getPID("d3lphin");
		getPID("mousepad");
	}

	return 0;
}

root@Csabi:~/qtproj/build-pidfind-Desktop_Qt_5_3_0_GCC_64bit-Debug# time pidfind_tch

real    0m1.729s
user    0m0.264s
sys     0m1.424s
root@Csabi:~/qtproj/build-pidfind-Desktop_Qt_5_3_0_GCC_64bit-Debug# time pidfind_kemi

real    1m9.365s
user    0m23.216s
sys     0m29.176s