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问题描述
简单的fopen操作似乎不起作用。 PERROR回报 - 参数无效。什么可能是错误的。
我有R中称为abc.dat一个ASCII文件：
INT的main（）
{
FILE * F =的fopen（R：\\ abc.dat，R）;
如果（！F）
{
PERROR（出现以下错误）; 返回1;
}
}
输出：
解决方案
Escape your \. It must be \\ when used in the string.
FILE *f = fopen("R:\\abc.dat","r");
Otherwise, the string is seen by fopen to be including the \a "alert" escape sequence which is an invalid argument to it.
Common escape sequences and their purposes are:
\a The speaker beeping
\\ The backslash character
\b Backspace (move the cursor back, no erase)
\f Form feed (eject printer page; ankh character on the screen)
\n Newline, like pressing the Enter key
\r Carriage return (moves the cursor to the beginning of the line)
\t Tab
\v Vertical tab (moves the cursor down a line)
\’ The apostrophe
\" The double-quote character
\? The question mark
\0 The "null" byte (backslash-zero)
\xnnn A character value in hexadecimal (base 16)
\Xnnn A character value in hexadecimal (base 16)
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