I$Create modified by Lothan

Lothan — Fri, 27 Jun 2014 23:20:21 -0000

Create File
Creates and opens a disk file

OS9 I$Create 103F 83

Entry Conditions

A access mode (write or update)

B file attributes

X address of the pathlist

Exit Conditions

A path number

X address of the last byte of the pathlist + 1; skips any trailing blanks

Error Output

CC carry set on error

B error code, if any

Additional Information

NitrOS-9 parses the pathlist and enters the new filename in the specified directory. If you do not specify a directory, NitrOS-9 enters the new filename in the working directory.
NitrOS-9 gives the file the attributes passed in Register B, which has bits defined as follows:

Bit
Definition

0
Read

1
Write

2
Execute

3
Public read

4
Public write

5
Public execute

6
Shareable file

These access mode parameters passed in Register A must have the write bit set if any data is to be written. These access codes are defined as follows: 2 = write, 3 = update. The mode affects the file only until the file is closed.
You can reopen the file in any access mode allowed by the file attributes. (See the Open system call.)
Files opened for write can allow faster data transfer than those opened for update because update sometimes needs to pre-read sectors.
If the execute bit (Bit 2) is set, the file is created in the working execution directory instead of the working data directory.
Create File causes an implicit I$Attach call. If the device has not previously been attached, the device’s initialization routine is called.
Later I/O calls use the path number to identify the file, until the file is closed.
NitrOS-9 does not allocate data storage for a file at creation. Instead, it allocates the storage either automatically when you first issue a write or explicitly by the SetStat subroutine.
If the filename already exists in the directory, an error occurs. If the call specifies a non-multiple file device (such as a printer or terminal), Create behaves the same as Open.
You cannot use Create to make directories. (See the Make Directory system call for instructions on how to make directories.)
Before the Create File call:

/
D
0
/
W
O
R
K
$0D

/
D
0
/
W
O
R
K
$0D

Recent changes to I$Create