gzseek

(PHP 3, PHP 4, PHP 5)

gzseek -- Seek on a gz-file pointer

说明

int gzseek ( resource zp, int offset )

Sets the file position indicator for the given file pointer to the given offset byte into the file stream. Equivalent to calling (in C) gzseek(zp, offset, SEEK_SET).

If the file is opened for reading, this function is emulated but can be extremely slow. If the file is opened for writing, only forward seeks are supported; gzseek() then compresses a sequence of zeroes up to the new starting position.

参数

zp

The gz-file pointer. It must be valid, and must point to a file successfully opened by gzopen().

offset

The seeked offset.

返回值

Upon success, returns 0; otherwise, returns -1. Note that seeking past EOF is not considered an error.

范例

例子 1. gzseek() example

<?php
$gz
= gzopen('somefile.gz', 'r');
gzseek($gz,2);
echo
gzgetc($gz);
gzclose($gz);
?>

参见

gztell()
gzrewind()