读取正在更改的文件
提供了以下示例代码：
<?php
$handle = fopen("/tmp/test_file/sometestfile", "r");
$contents = '';
while (!feof($handle)) {
$contents = fread($handle, 10);
print $contents;
sleep(1);
}
fclose($handle);
?>
如果 sometestfile（在我的例子中是一个 txt 文件）在读取循环期间发生更改，为什么 php 程序继续从旧文件中读取？ 假设它充满了 1，我将 sometestfile_new 覆盖在它上面，它充满了 2。 我在 Linux 上运行这个，这个 inode 相关吗？ 如果在每个循环之后添加 rewind() ，则在覆盖时间点之后将读取新文件。
Provided the following example code:
<?php
$handle = fopen("/tmp/test_file/sometestfile", "r");
$contents = '';
while (!feof($handle)) {
$contents = fread($handle, 10);
print $contents;
sleep(1);
}
fclose($handle);
?>
If sometestfile, which is a txt file in my case, changes during the read loop, why is the php program continuing to read from the old file?
Say it is full of 1's and I cat sometestfile_new over it which is full of 2's.
I am running this on Linux, is this inode related?
If rewind() is added after each loop, the new file will be read instead, after the overwrite point in time.
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来自 php.net
fopen()绑定一个命名的由filename指定的资源到流。fopen()一旦被调用，它就会“缓存”文件，并将在您提到的方法中输出，例如您的$contents = fread($handle, 10);您可以删除该文件，它仍然会读取该资源，直到完成该文件
!feof($handle)您不能使用
fopen()执行任何其他操作，您只是无法重读源代码继续打印它。from php.net
fopen()binds a named resource, specified byfilename, to a stream.the
fopen()as soon as it's called it "caches" the file and will output in the method you mention, example is your$contents = fread($handle, 10);You can delete the file and it will still read that resource until it finishes the file
!feof($handle)You cannot do anything else with
fopen(), you just can't reread the source and continue to print it.