Open System Services System Calls Reference Manual (G06.29+, H06.08+, J06.03+)

System Functions (a - d) creat(2)
File Type Flags
The file type flags that can be logically ORed into the value specified in the mode parameter are:
S_IFREG Regular file in the OSS file system or in /G, the Guardian file system.
S_ISVTX Sticky bit; used only for directories (cannot be used for files in /G, the Guardian
file system).
Access Control Lists (ACLs)
The creat() function does not change the ACL for an existing file. For more information about
ACLs for existing files, see the acl(2), chmod(2), and acl(5) reference pages.
For more information about ACLs, including ACL inheritance for newly created files, see the
acl(5) reference page.
Opening Guardian Files
If the file is a Guardian file (that is, a file in the /G file system), these rules apply:
• The file can be opened only if it is one of these:
— An odd, unstructured Enscribe file. In this case, it is opened as a regular file with
a primary and secondary extent size that is a multiple of 2. If the extent size is
odd, the open fails.
If the unstructured buffer size was not 4096, a successful open makes the buffer
size 4096 (as if the Guardian procedure SETMODE was called for mode 93 with
a parameter value of 4096).
— An EDIT file (file code 101). In this case, it is opened as a regular file for read-
only access.
— A tty simulation process.
An attempt to open any file (or device) of any other type fails, and errno is set to the
value of [EINVAL].
An attempt to open any file on a logical disk volume (virtual disk) administered through
the Storage Management Foundation (SMF) fails, and errno is set to the value of
[ENOTSUP].
An attempt to open a volume, subvolume, or process (/G/vol, /G/vol/subvol,or
/G/process, respectively) fails, and errno is set to the value of [EISDIR].
• An attempt to open a subvolume with a reserved name beginning with "ZYQ" (for exam-
ple, /G/vol2/zyq00004) fails, and errno is set to the value of [EACCES].
• An attempt to open a file within a subvolume with a reserved name beginning with
"ZYQ" (for example, /G/vol2/zyq00004/z000002x) fails, and errno is set to the value of
[EACCES].
• If the file is not an EDIT file (that is, the file code is not 101), it is opened in shared
exclusion mode.
• If the file is an EDIT file and read-only access is specified, the file is opened in protected
exclusion mode in the Guardian environment.
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