INF: Locating Subdirectory with _dos_findfirst & _dos_findnext

ID Number: Q43144

5.x 6.00 6.00a 6.00ax 7.00 | 5.10 6.00 6.00a

MS-DOS | OS/2

Summary:

In Microsoft C versions 5.0, 5.1, 6.0, 6.0a, 6.0ax, and C/C++ version

7.0, when the attribute argument to the _dos_findfirst() and

_dos_findnext() functions is either _A_RDONLY, _A_HIDDEN, _A_SYSTEM,

or _A_SUBDIR, the functions will return all normal-attribute files. A

normal-attribute file is any file that does not have a read-only,

hidden, system, or directory attribute.

Thus, the following function call will return either a normal file or

a subdirectory:

_dos_findfirst( "*.*", _A_SUBDIR, &c_file )

More Information:

To verify that the returned c_file is a subdirectory, check the

attribute field of the c_file to determine whether the _A_SUBDIR bit

is set. If so, then it is a subdirectory. This process may be

accomplished by doing a bitwise-and of c_file.attrib with _A_SUBDIR

and checking for a nonzero result.

The following program illustrates the use of these functions:

#include <dos.h>

#include <stdio.h>

main()

{

struct find_t c_file;

_dos_findfirst( "*.*", _A_SUBDIR, &c_file );

if( c_file.attrib & _A_SUBDIR )

printf( "Directory listing %s\n", c_file.name );

while (_dos_findnext(&c_file) == 0)

if( c_file.attrib & _A_SUBDIR )

printf( "Directory listing %s\n", c_file.name );

}

Additional reference words: 5.10 6.00 6.00a 6.00ax 7.00