Open()

 #include <stdio.h>

#include<stdlib.h>

#include<string.h>

#include <fcntl.h>

main(int argc, char *argv[])

{

int fd, n, len;char buf[100];

if (argc != 2)

{

printf("Usage: ./a.out <filename>\n");exit(-1);

}

fd = open(argv[1], O_WRONLY|O_CREAT|O_TRUNC, 0644);if(fd < 0)

{

printf("File creation problem\n");exit(-1);

}

printf("Press Ctrl+D at end in a new line:\n");while((n = read(0, buf, sizeof(buf))) > 0)

{

len = strlen(buf); write(fd, buf, len);

}

close(fd);

}

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