マルチスレッドは複数のファイルの単語数を統計します.

#include<stdio.h>
#include<stdlib.h>
#include<pthread.h>
#include<stdbool.h>

#define filenumbers 3//      
#define filenamenum 256//        256
int cal(char filename[256]);
void *thread_function(void *arg);

int wordcount=0;//         
int count[3]={0,0,0};//            0
char filenames[filenumbers][filenamenum]={"file1","file2","file3"};

pthread_mutex_t  fileMutex;//        
int main()
{	int i=0;
	int flag;//           
	pthread_t thread[3];
//	int count1=0,count2=0,count3=0;

	/*      */
	flag=pthread_mutex_init(&fileMutex,NULL);
	if(flag!=0)
	{
		perror("Mutex initalization failed!
");
		return 1;
	}

	/*create pthread*/
	for(i=0;i<3;i++)
	{
		flag=pthread_create(&thread[i],NULL,thread_function,(void*)&filenames[i]);
		if(flag!=0)
		{
			perror("Thread creation failed!
");
			return 1;
		}
	}


	//pthread_join(thread[0],(void**)&count1);
	//pthread_join(thread[1],(void**)&count2);
	//pthread_join(thread[2],(void**)&count3);
	for(i=0;i<3;i++)
	{
		pthread_join(thread[i],(void**)&count[i]);
	}

	wordcount=count[0]+count[1]+count[2];
	printf("     :%d
",wordcount);
	return 0;
}





int cal(char filename[256])
{
	bool start;
	int count=0;//       
	char c;
	long int offset;
	FILE *fp;
	fp=fopen(filename,"r");
	if(fp==NULL)
	{
		printf("open filed!
");
		exit(EXIT_FAILURE);
	}

	fseek(fp,0,SEEK_SET);
	start=true;//start=0         ,start=1    
	while(feof(fp)==0)//feof(fp)==0          
	{
		fread(&c,1,1,fp);
		if(c==' '&&start==1)
		{
			start=1;
		}
		else if(c!=' '&&start==1)
		{
			start=0;
			count++;
		}
		else if(c==' '&&start==0)
		{
			start=1;
		}
	}
	printf("%s",filename);
	printf("word count:%d
",count);
	return count;
}
void *thread_function(void *arg)
{
		return (void*)cal((char*)arg);
}