Module Name: src
Committed By: christos
Date: Sun Sep 15 20:53:24 UTC 2019
Modified Files:
src/lib/libc/sys: open.2
Log Message:
Document O_EXEC, and add some extra explanation for O_CREAT from FreeBSD.
To generate a diff of this commit:
cvs rdiff -u -r1.60 -r1.61 src/lib/libc/sys/open.2
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/libc/sys/open.2
diff -u src/lib/libc/sys/open.2:1.60 src/lib/libc/sys/open.2:1.61
--- src/lib/libc/sys/open.2:1.60 Sun Sep 1 19:57:14 2019
+++ src/lib/libc/sys/open.2 Sun Sep 15 16:53:24 2019
@@ -1,4 +1,4 @@
-.\" $NetBSD: open.2,v 1.60 2019/09/01 23:57:14 sevan Exp $
+.\" $NetBSD: open.2,v 1.61 2019/09/15 20:53:24 christos Exp $
.\"
.\" Copyright (c) 1980, 1991, 1993
.\" The Regents of the University of California. All rights reserved.
@@ -29,13 +29,13 @@
.\"
.\" @(#)open.2 8.2 (Berkeley) 11/16/93
.\"
-.Dd September 2, 2019
+.Dd September 16, 2019
.Dt OPEN 2
.Os
.Sh NAME
.Nm open ,
.Nm openat
-.Nd open or create a file for reading or writing
+.Nd open or create a file for reading, writing or executing
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
@@ -48,15 +48,34 @@
The file name specified by
.Fa path
is opened
-for reading and/or writing as specified by the
+for either execution or reading and/or writing as specified by the
argument
.Fa flags
and the file descriptor returned to the calling process.
+The
+.Fa flags
+argument may indicate the file is to be
+created if it does not exist (by specifying the
+.Dv O_CREAT
+flag).
+In this case
+.Fn open
+and
+.Fn openat
+require an additional argument
+.Fa "mode_t mode" ,
+and the file is created with mode
+.Fa mode
+as described in
+.Xr chmod 2
+and modified by the process' umask value (see
+.Xr umask 2 ) .
.Pp
+The
.Fn openat
-works the same way as
+function is equivalent to the
.Fn open
-except if
+function except in the case where the
.Fa path
is relative.
In that case, it is looked up from a directory whose file
@@ -91,6 +110,8 @@ Applications must specify exactly one of
Open for reading only.
.It Dv O_WRONLY
Open for writing only.
+.It Dv O_EXEC
+Open for execute only.
.It Dv O_RDWR
Open for reading and writing.
.El
@@ -412,6 +433,14 @@ In addition,
.Fn openat
will fail if:
.Bl -tag -width Er
+.It Bq Er EINVAL
+An attempt was made to open a descriptor with an illegal combination
+of
+.Dv O_RDONLY ,
+.Dv O_WRONLY ,
+.Dv O_RDWR
+and
+.Dv O_EXEC .
.It Bq Er EBADF
.Fa path
does not specify an absolute path and
