判断文件是否存在

Determine file-access permission.

int _access( const char *path, int mode );

mode Value	Checks File For
00	Existence only
02	Write permission
04	Read permission
06	Read and write permission

头文件 #include

Example

/* ACCESS.C: This example uses _access to check the
 * file named "ACCESS.C" to see if it exists and if
 * writing is allowed.
 */

#include  
#include  
#include  

void main( void )
{
   /* Check for existence */
   if( (_access( "ACCESS.C", 0 )) != -1 )
   {
      printf( "File ACCESS.C exists\n" );
      /* Check for write permission */
      if( (_access( "ACCESS.C", 2 )) != -1 )
         printf( "File ACCESS.C has write permission\n" );
   }
}

Output

File ACCESS.C exists
File ACCESS.C has write permission