我想实现对已有文件中的部分内容的修改，比如文件中的"abcdef"我想修改为"cbadef"，其余位置的文件内容不做更改，并且将结果存到原文件中，请问应该如何操作?
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Just rewrite it, it will overwrite the original
Use the lseek(int filedes, off_t offset, int whence) function to operate with the offset of the file pointer
To overwrite without changing the file length, just lseek directly
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Just rewrite it, it will overwrite the original
Use the lseek(int filedes, off_t offset, int whence) function to operate with the offset of the file pointer
To overwrite without changing the file length, just lseek directly