dup를 이용한 파일지정번호 복사

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#include <unistd.h> 
int dup(int oldfd);
int dup2(int oldfd, int newfd);
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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[root@localhost test]# cat < test.txt
dark rain.
...
...
[root@localhost test]# 
 
 
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#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <vector>
#include <string>
#include <sys/types.h>
#include <sys/wait.h>
#include <algorithm>
#include <fcntl.h>
vector<string> makearg(string);
int main()
{
    char *buf;
    vector<string> arg;
    int pid = 0;
    int fd;
    int redirect = 0;
    // SIGCHLD 시그널을 무시한다. 
    signal(SIGCHLD, SIG_IGN);
    buf = (char *)malloc(sizeof(char) *255);
    while(1)
    {
        redirect = 0;
        memset (buf, 0x00, 255);
        // 사용자 입력대기용 프롬프트를 띄운다.
        write(1, "# ", 3);
        if (read(0, buf, 255) > 1)
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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[root@s210-205-210-195 dup]# ./dup3
# ls
dump  dup1  dup1.c  dup2  dup2.c  dup3  dup3.c  sh  sh.c
# tail < dup3.c
                if (*mi == ' ') 
                        str.erase(mi);
                *mi++;
        }
        num = str.find("<");
        return_str.push_back(str.substr(0,num));
        return_str.push_back(str.substr(num+1));
        return return_str;
}
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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