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文本文件中的 NULL 终止符

[英]NULL Terminator in text files

原文 2016-12-01 20:44:08 8 1 c/ input/ command-line/ null-terminated

I am creating a program that reads in the contents of a text file through the command line, character by character.我正在创建一个程序，该程序通过命令行逐个字符地读入文本文件的内容。

Is the NULL value automatically inserted or do I have to add it to the text file manually? NULL 值是自动插入还是我必须手动将其添加到文本文件中？

1 个解决方案

Text files do not need to have a terminator on modern platforms.在现代平台上，文本文件不需要有终止符。 (On some legacy platforms they did have one, but I doubt it is the case here.) You almost certainly should not write a terminator into the file, as it may cause problems with programs that do not expect one. （在一些遗留平台上他们确实有一个，但我怀疑这里的情况。）您几乎肯定不应该在文件中写入终止符，因为它可能会导致不期望终止符的程序出现问题。 The end of file serves as a terminator when reading.文件末尾在读取时用作终止符。

Text strings in C are arrays of characters terminated by a zero, aka the null character, mnemonic NUL (with one L, and it is not the same thing as NULL in C). C 中的文本字符串是以零结尾的字符数组，也就是空字符，助记符 NUL（带有一个 L，它与 C 中的NULL ）。 When creating strings, you do need to terminate them correctly.创建字符串时，您确实需要正确终止它们。 Functions returning strings, including ones that read them from files (eg, fgets ), terminate them for you.返回字符串的函数，包括从文件中读取它们的函数（例如fgets ），会为您终止它们。