pSOSystem System Calls - Read

open_f pHILE+ System Calls
open_f Opens a file.
#include
unsigned long open_f(
unsigned long *fid, /* file identifier */
char *name, /* pathname */
unsigned long mode /* unused; set to zero */
)
Volume Types
Description
Arguments
Return Value
All volume types.
open_f() creates a connection between a file and the calling task and returns a file
identifier. The file identifier is used in subsequent operations on the file. open_f()
fails if the system is out of file control blocks or if the task is out of open file table
entries.
open_f() does not check for a file type. It opens ordinary files, directory files, or
system files. However, directory files and system files are read-only.
open_f() always positions the L_ptr at the first byte in the file.
For CD-ROM volumes, open_f() can be used to read the primary volume descriptor.
See “Primary Volume Descriptor,” under “Notes.”
fid Points to the variable where open_f() stores the file identifier.
name Points to the null-terminated pathname of the file to open.
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.
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