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readv

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#include <sys/uio.h>



ssize_t readv(int fd, const struct iovec *iov, int iovcnt);



ssize_t writev(int fd, const struct iovec *iov, int iovcnt);

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¥Ý¥¤¥ó¥¿ iov ¤Ï iovec ¹½Â¤ÂΤÎÇÛÎó¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£ iovec ¹½Â¤ÂÎ¤Ï <sys/uio.h> ¤Ç°Ê²¼¤Î¤è¤¦¤ËÄêµÁ¤µ¤ì¤Æ¤¤¤ë:

struct iovec {

    void  *iov_base;    /* Starting address */

    size_t iov_len;     /* Number of bytes to transfer */

};

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°Ê²¼¤Î¥µ¥ó¥×¥ë¥³¡¼¥É¤Ï writev() ¤Î»ÈÍÑÊýË¡¤ò¼¨¤¹¤â¤Î¤Ç¤¢¤ë¡£

char *str0 = "hello ";

char *str1 = "world\n";

struct iovec iov[2];

ssize_t nwritten;



iov[0].iov_base = str0;

iov[0].iov_len = strlen(str0);

iov[1].iov_base = str1;

iov[1].iov_len = strlen(str1);



nwritten = writev(STDOUT_FILENO, iov, 2);

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read(2), write(2)