#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include?

#define?THREADS_COUNT?4
#define?THREADS_BUFF_SIZE?1*1024
struct?thread_block
{
????int?infd;?///源文件句柄
????int?outfd;//目的文件句柄
????size_t?start;///文件的寫(xiě)入起始位置
????size_t?end;?///文件寫(xiě)入的終止位置
};

void?usage（）
{
????printf（“copy?%%src?%%dst\n“）;
}
///獲取文件大小
size_t?get_filesize（int?fd）
{
????struct?stat?st;
????fstat（fd&st）;
????return?st.st_size;
}
void?*thread_copy_fn（void?*arg）
{
????struct?thread_block?*block?=?（struct?thread_block?*）arg;
????char?buf[THREADS_BUFF_SIZE];????
????int?ret;
????size_t?count?=?block->start;

????printf（“In?Thread\t%ld\nstart?=?%d\t?end?=?%d\n“\
????????????pthread_self（）block->startblock->end）;

????///lseek到同樣的位置
????ret?=?lseek（block->infdblock->startSEEK_SET）;
????ret?=?lseek（block->outfdblock->startSEEK_SET）;
????int?bytes_read;
????int?bytes_write;
????while（count?end）
????{
????????bytes_read?=?read（block->infdbufsizeof（buf））;
????????if（bytes_read?>0）
????????{
????????????printf（“thread?=?%ld\t?read?=?%d\t?count?%d\n“\
????????????????????pthread_self（）bytes_readcount）;
????????????count?+=?bytes_read;

????????????//read（）返回-1，同時(shí)errno為EINTR，表示讀的過(guò)程中遇到了中斷
????????????if（（bytes_read?==?-1）&&（errno?!=EINTR））
????????????????????break;
????????????char?*ptr_write?=?buf;
????????????while（（bytes_write?=?write（block->outfdptr_writebytes_read））!=0）
????????????{
????????????????//write（）會(huì)返回-1，同時(shí)errno為EINTR，表示在寫(xiě)的過(guò)程中遇到了中斷
????????????????if（（bytes_write?==?-1）&&（errno!=EINTR））
????????????????????break;
????????????????if（bytes_write?==?bytes_read）
????????????????????break;
????????????????else?if（bytes_write?>?0）
????????????????{
????????????????????ptr_write?+=?bytes_write;
????????????????????bytes_read?-=?bytes_write;
????????????????}
????????????????printf（“thread?=?%ld\t?write?=?%d\t?read?%d\n“\
????????????????????pthread_self（）bytes_writebytes_read）;
????????????}//end-write;
????????????///error?while?write
????????????if（bytes_write?==?-1）
????????????????break;
????????????
????????}
????}
????printf（“#####Thread?exit?%ld#####\n“pthread_self（））;
????pthread_exit（NULL）;?
}?
int?main（int?argcchar?*argv[]）
{
????if（argc?????{
????????usage（）;????
????????return?-1;
????}
????///打開(kāi)文件
????int?infd?=?open（argv[1]O_RDONLY）;
????int?outfd?=?open（argv[2]O_CREAT|O_WRONLY0644）;
????//?0644也就是-文件所有者有讀寫(xiě)權(quán)限，組有讀權(quán)限，其他用戶有讀權(quán)限
????if（infd?==?-1||?-1?==outfd）
????{
????????printf（“error?while?open?file?\n“）;
????????return?-1;
????}
????size_t?file_size?=?get_filesize（infd）;

????size_t?thread_size?=?THREADS_COUNT;
????struct?thread_block?*blocks?=?（struct?thread_block?*）
????????malloc（sizeof（struct?thread_block?）*?thread_size）;
????size_t?percent?=?file_size?/?thread_size;
????printf（“filesize?=?%d\t?percent_blocks?=?%d\n“\
????????????file_sizepercent）;
????int?i?=?0;

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----

?????文件????????383??2014-06-11?17:00??C實(shí)現(xiàn)多線程下載源碼\readme.txt.txt

?????文件???????3911??2014-06-11?16:07??C實(shí)現(xiàn)多線程下載源碼\thread_download.c

?????目錄??????????0??2014-06-11?16:59??C實(shí)現(xiàn)多線程下載源碼

-----------?---------??----------?-----??----

?????????????????4294????????????????????3