int pid_lseek ( int $pid, int $offset [ , int $whence = SEEK_SET ] )
pid_lseek() перемещает read/write смещаения PID
Возращает смещение от начала, при ошибке PHP появится error.
<?php
$buf = "ABCDEFGHIJKLMNOPabcdefghijklmnop";
$pid_um = pid_open("/mmap/um1"); // /mmap/um1 buffer size is 64
pid_lseek($pid_um, 0, SEEK_SET); // set the point to the beginning (position 0)
pid_write($pid_um, $buf, 32); // write $buf to the position 0 (position changed to 32 after this operation)
pid_lseek($pid_um, 0, SEEK_SET); // set the point to the beginning (position 0)
pid_read($pid_um, $buf, 32); // read 32 bytes from the current position (position 0)
hexdump($buf); // outputs $buf
// OUTPUT
// 0000 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f 50 |ABCDEFGHIJKLMNOP|
// 0010 61 62 63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f 70 |abcdefghijklmnop|
pid_lseek($pid_um, 0, SEEK_SET); // set the point to the beginning (position 0)
pid_lseek($pid_um, 8, SEEK_CUR); // set the point to position 8
pid_read($pid_um, $buf, 16); // read 16 bytes from the current position (position 8)
hexdump($buf); // outputs $buf
// OUTPUT
// 0000 49 4a 4b 4c 4d 4e 4f 50 61 62 63 64 65 66 67 68 |IJKLMNOPabcdefgh|
pid_read($pid_um, $buf, 16); // read 16 bytes from the current position (position 24)
hexdump($buf);
// OUTPUT
// 0000 69 6a 6b 6c 6d 6e 6f 70 00 00 00 00 00 00 00 00 |ijklmnop........|
pid_lseek($pid_um, -48, SEEK_END); // set the point to 48 from the end (position 16)
pid_read($pid_um, $buf, 16); // read 16 bytes from the current position (position 16)
hexdump($buf); // outputs $buf
// OUTPUT
// 0000 61 62 63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f 70 |abcdefghijklmnop|
?>
pid_open() / pid_close() / pid_ioctl() / pid_read() / pid_write() /
Отсутствуют.