1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
|
.TH CREAT 2
.CT 2 file_inq_creat
.SH NAME
creat, bcreat \(mi create a new file
.SH SYNOPSIS
.nf
.B int creat(name, mode)
.B char *name;
.PP
.B int bcreat(name, mode, name2)
.B char *name, name2[14];
.fi
.SH DESCRIPTION
.I Creat
creates a new file or prepares to rewrite an existing
file called
.I name,
given as the address of a null-terminated string.
If the file is new, its inode is initialized as follows.
The owner of the file is the effective userid of the creating process.
The group of the file is the group of the containing directory.
The mode of the file is
.IR mode ,
as modified by the process's mode mask; see
.IR umask (2).
Setgid is turned off if the effective groupid of
the process differs from the groupid of the file.
See
.IR stat (2)
for the encoding of modes.
.PP
If the file did exist, its mode and owner remain unchanged.
The file is truncated to 0 length unless it is append-only; see
.IR stat (2).
.PP
The file is opened for writing, and its file descriptor
is returned.
.PP
The
.I mode
given is arbitrary; it need not allow
writing.
This feature is used by programs which deal with temporary
files of fixed names.
The file is created with
a mode that forbids writing.
Then if a second
instance of the program attempts a
.I creat,
an error is
returned and the program knows that the name is unusable
for the moment.
.PP
.I Bcreat
performs the function of
.I creat,
and then, if successful, copies the last component of the actual
pathname of the created file as a NUL-padded string into
.I name2.
It is intended for use with blind directories, where new
entries are created under random names; see
.IR mkdir (2).
.PP
It is not possible to create or open for writing
a file with set-userid or set-groupid permission; see
.IR stat (2).
.SH "SEE ALSO"
.IR chmod (2),
.IR close (2),
.IR umask (2),
.IR write (2)
.SH DIAGNOSTICS
.L
EACCES, EBADF, EBUSY, EFAULT, EIO, EISDIR, ELAB, ELOOP, EMFILE, ENFILE, ENOENT, ENOTDIR, EROFS, ETXTBSY
|
