请问：怎么从某一确定的行开始读文件？

ddvv

一个看似简单的问题，原来还有那么多学问。。。。。。这里让我知道了一些我原来没有注意的东西，比如read不保险~
继续关注。

LinuxFresh

Mark

yecheng_110

原帖由 flw 于 2007-4-7 17:23 发表

你看的是哪一版？
我这里有一份电子的，我看了一下，第 4.2 节讲的是 stat fstat 和 lstat 啊。没有说 read。
考虑到你有可能是 4.20 节的手误，我还特意看了一下，讲的是 mkdir。

《unix 高级环境编程》14.8

14.8. readn and writen Functions
Pipes, FIFOs, and some devices, notably terminals, networks, and STREAMS devices, have the following two properties.

A read operation may return less than asked for, even though we have not encountered the end of file. This is not an error, and we should simply continue reading from the device.

A write operation can also return less than we specified. This may be caused by flow control constraints by downstream modules, for example. Again, it's not an error, and we should continue writing the remainder of the data. (Normally, this short return from a write occurs only with a nonblocking descriptor or if a signal is caught.)

We'll never see this happen when reading or writing a disk file, except when the file system runs out of space or we hit our quota limit and we can't write all that we requested.

yecheng_110

原帖由 flw 于 2007-4-7 17:23 发表

你看的是哪一版？
我这里有一份电子的，我看了一下，第 4.2 节讲的是 stat fstat 和 lstat 啊。没有说 read。
考虑到你有可能是 4.20 节的手误，我还特意看了一下，讲的是 mkdir。

《unix 高级环境编程2》14.8

14.8. readn and writen Functions
Pipes, FIFOs, and some devices, notably terminals, networks, and STREAMS devices, have the following two properties.

A read operation may return less than asked for, even though we have not encountered the end of file. This is not an error, and we should simply continue reading from the device.

A write operation can also return less than we specified. This may be caused by flow control constraints by downstream modules, for example. Again, it's not an error, and we should continue writing the remainder of the data. (Normally, this short return from a write occurs only with a nonblocking descriptor or if a signal is caught.)

We'll never see this happen when reading or writing a disk file, except when the file system runs out of space or we hit our quota limit and we can't write all that we requested.

Godbach

默默的学习，然后赞一把

JohnBull

考虑兼容性和可移植性的话，还是应该使用stdio来实现。

还是用fgets吧！

Godbach

从以上讨论来看，是不是每次只取一个字符，然后判断，是最有效的一种方法呢？

star65225692

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wangqi0021

原帖由 star65225692 于 2008-3-17 15:30 发表
星辰技术社区:www.netcsharp.cn,您将获得最新,最全的.NET技术信息.您将时刻掌握最前沿的.NET技术动向~~~欢迎您的加入

这个时候出现一则广告 有点搞笑了