pSOSystem System Calls - Read

pHILE+ System Calls open_fn
open_fn Opens a file by its file identifier.
#include
unsigned long open_fn(
unsigned long *fid, /* file identifier */
char *device, /* volume name */
unsigned long fn, /* file number */
unsigned long mode /* unused, set to 0 */
)
Volume Types
Description
Arguments
Return Value
pHILE+, MS-DOS, and CD-ROM formatted volumes.
open_fn() functions identically to open_f() except that open_fn() opens a file
associated with a specified file number. The file number is first obtained with
get_fn().
open_fn() is more efficient than open_f() when a particular file is frequently
opened, since open_fn() skips pathname parsing and directory searching.
fid Points to the variable where open_fn() stores the file identifier.
device Points to the null-terminated name of the volume containing the
file.
fn The file number of the file.
mode Reserved for future use; should be set to 0 for future compatibility.
This system call returns 0 on success or an error code on failure.
pSOSystem System Calls 2-83
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