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z*i2004-09-30 07:09

1 楼

读数据从文件中，
input=fopen(filename,"rb");
while ( (c=fgetc(input)) != EOF )
{
}
可是数据中有0xff, 255(int)好像这个被当成eof了，请问有什末办法读出来吗?

f*g2004-09-30 07:09

2 楼

use fstat/stat to count your file's size. read
the size of byte instead of checking if EOF is reached.

【在 z********i 的大作中提到】

: 读数据从文件中，
: input=fopen(filename,"rb");
: while ( (c=fgetc(input)) != EOF )
: {
: }
: 可是数据中有0xff, 255(int)好像这个被当成eof了，请问有什末办法读出来吗?

g*e2004-09-30 07:09

3 楼

what is the type of c? int or char?
if char, you get into trouble because
-1 is same as 0xff in char.

【在 z********i 的大作中提到】

: 读数据从文件中，
: input=fopen(filename,"rb");
: while ( (c=fgetc(input)) != EOF )
: {
: }
: 可是数据中有0xff, 255(int)好像这个被当成eof了，请问有什末办法读出来吗?

s*e2004-09-30 07:09

4 楼

agree, this code is wrong.

【在 g*******e 的大作中提到】

: what is the type of c? int or char?
: if char, you get into trouble because
: -1 is same as 0xff in char.

Q*g2004-09-30 07:09

5 楼

what's the data type of variable c? if it's int, the code should be fine.
if it's char, you may get a problem coz you can not differentiate EOF
and 0xff. the following paragraph is extracted from GNU C library:
These functions return an int or wint_t value (for narrow and wide stream
functions respectively) that is either a character of input, or the special
value EOF/WEOF (usually -1). For the narrow stream functions it is
important to store the result of these functions in a variable of type i

【在 z********i 的大作中提到】

: 读数据从文件中，
: input=fopen(filename,"rb");
: while ( (c=fgetc(input)) != EOF )
: {
: }
: 可是数据中有0xff, 255(int)好像这个被当成eof了，请问有什末办法读出来吗?

z*i2004-09-30 07:09

6 楼

Thank, already done with Java, will try later for C.
My former definition is
char c, changing to unsigned int c works. Thank you

【在 s*****e 的大作中提到】

: agree, this code is wrong.