Question

C语言指针问题，求详解！！

设fp为指向某二进制文件的指针，且已读到此文件末尾，则函数feof（fp)的返回值为
A.EOFB B.非0值 C.0 D.NULL

Answer 1

feofSee Alsoclearerr
| ferror

Requirements
OS Versions: Windows CE 2.0 and later.
Header:
stdlib.h.
Link Library: coredll.dll.
Tests for end-of-file on a stream.
int feof( FILE* stream
);Parametersstream
Pointer to FILE structure. Return Values
The feof function returns a nonzero value after the first read
operation that attempts to read past the end of the file.
It returns 0 if the current position is not end of file.
There is no error return.
Remarks
The feof routine (implemented both as a function and as a macro)
determines whether the end of stream has been reached.
When end of file is reached, read operations return an end-of-file indicator
until the stream is closed or until fsetpos, fseek, or
clearerr is called against it.
Example
/* FEOF.C: This program uses feof to indicate when
* it reaches the end of the file FEOF.C. It also
* checks for errors with ferror.
*/

#include <stdio.h>
#include <stdlib.h>

void main( void )
{
int count, total = 0;
char buffer[100];
FILE *stream;

if( (stream = fopen( "feof.c", "r" )) == NULL )
exit( 1 );

/* Cycle until end of file reached: */
while( !feof( stream ) )
{
/* Attempt to read in 10 bytes: */
count = fread( buffer, sizeof( char ), 100, stream );
if( ferror( stream ) ) {
printf( "Read error" );
break;
}

/* Total up actual bytes read */
total += count;
}
printf( "Number of bytes read = %d\n", total );
fclose( stream );
}
Output
Number of bytes read = 745Requirements
OS Versions: Windows CE 2.0 and later.
Header:
stdlib.h.
Link Library: coredll.dll.
See Also
clearerr | ferror

Last updated on Wednesday, September 14, 2005
© 2005
Microsoft Corporation. All rights reserved.

Answer 2

B.

feof 就是检测 当前fp打开的文件 指针是否在文件的最后面。到了结尾肯定返回非0

Answer 3

B
如果到了文件尾，表明是，返回非零

Answer 4

30分钟彻底学会C语言指针

Answer 5

b