What does fopen stand for in c language

fopen is a function in C language used to open a file. It accepts the file path and mode as parameters and returns a pointer to the file. Available modes are read-only ("r"), write-only ("w"), append ("a"), and read-write ("r", "w", "a"). A pointer to the FILE object is returned on successful file opening, or NULL on failure.

The meaning of fopen in C language

fopen is a function defined in the C standard library for Opens a file and returns a pointer to the file of type FILE.

Function prototype

<code class="c">FILE *fopen(const char *path, const char *mode);</code>

Parameters

• path: The path of the file to be opened .

• mode: Specify the open mode, you can choose the following values:

  • "r": Read-only open
  • "w ": Open for writing only, create if the file does not exist
  • "a": Open for append writing, create if the file does not exist
  • "r ": Open for reading and writing, the file must exist
  • "w ": Open for reading and writing, create if the file does not exist
  • "a ": Open for reading and writing, create if the file does not exist

Return value

• If the file is opened successfully, a pointer to the FILE type object is returned.
• If opening the file fails, return NULL.

Usage

The fopen function is often used in the following scenarios:

• Read file content
• To file Write data in
• Update file content

Example

<code class="c">FILE *fp = fopen("test.txt", "r");
if (fp != NULL) {
    // 文件打开成功，可以读取文件内容
} else {
    // 文件打开失败，处理错误
}</code>

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