xnu-4903.270.47.tar.gz

[apple/xnu.git] / bsd / man / man2 / mkdir.2

diff --git a/bsd/man/man2/mkdir.2 b/bsd/man/man2/mkdir.2
index 4df68194d5049a24737ab2ed95a4bcb8f7af8fa9..24966225896de27db89e1a79f9d4c04134b7aaeb 100644 (file)
--- a/bsd/man/man2/mkdir.2
+++ b/bsd/man/man2/mkdir.2
@@ -37,7 +37,8 @@
 .Dt MKDIR 2
 .Os BSD 4.2
 .Sh NAME
-.Nm mkdir
+.Nm mkdir ,
+.Nm mkdirat
 .Nd make a directory file
 .Sh SYNOPSIS
 .Fd #include <sys/stat.h>
@@ -46,6 +47,8 @@
 .Fa "const char *path"
 .Fa "mode_t mode"
 .Fc
+.Ft int
+.Fn mkdirat "int fd" "const char *path" "mode_t mode"
 .Sh DESCRIPTION
 The directory
 .Fa path
@@ -53,17 +56,49 @@ is created with the access permissions specified by
 .Fa mode
 and restricted by the
 .Xr umask 2
-of the calling process.
+of the calling process. See
+.Xr chmod 2
+for the possible permission bit masks for
+.Fa mode . 
 .Pp
 The directory's owner ID is set to the process's effective user ID.
 The directory's group ID is set to that of the parent directory in
 which it is created.
+.Pp
+Note: the behavior of
+.Fn mkdir
+is undefined when mode bits other than the low 9 bits are used. Use
+.Xr chmod 2
+after
+.Fn mkdir
+to explicitly set the other bits (See example below).
+.Pp
+The
+.Fn mkdirat
+system call is equivalent to
+.Fn mkdir
+except in the case where
+.Fa path
+specifies a relative path.
+In this case the newly created directory is created relative to the
+directory associated with the file descriptor
+.Fa fd
+instead of the current working directory.
+If
+.Fn mkdirat
+is passed the special value
+.Dv AT_FDCWD
+in the
+.Fa fd
+parameter, the current working directory is used and the behavior is
+identical to a call to
+.Fn mkdir .
 .Sh RETURN VALUES
 A 0 return value indicates success.  A -1 return value
 indicates an error, and an error code is stored in
 .Va errno .
 .Sh ERRORS
-.Fn Mkdir
+.Fn mkdir
 will fail and no directory will be created if:
 .Bl -tag -width Er
 .\" ==========
@@ -96,6 +131,9 @@ or allocating the inode.
 .It Bq Er EIO
 An I/O error occurred while reading from or writing to the file system.
 .\" ==========
+.It Bq Er EISDIR
+The named file is the root directory.
+.\" ==========
 .It Bq Er ELOOP
 Too many symbolic links were encountered in translating the pathname.
 This is taken to be indicative of a looping symbolic link.
@@ -127,6 +165,45 @@ A component of the path prefix is not a directory.
 .It Bq Er EROFS
 The parent directory resides on a read-only file system.
 .El
+.Pp
+In addition to the errors returned by the
+.Fn mkdir ,
+the
+.Fn mkdirat
+function may fail if:
+.Bl -tag -width Er
+.It Bq Er EBADF
+The
+.Fa path
+argument does not specify an absolute path and the
+.Fa fd
+argument is neither
+.Dv AT_FDCWD
+nor a valid file descriptor open for searching.
+.It Bq Er ENOTDIR
+The
+.Fa path
+argument is not an absolute path and
+.Fa fd
+is neither
+.Dv AT_FDCWD
+nor a file descriptor associated with a directory.
+.El
+.Sh EXAMPLE
+.Bd -literal -offset indent
+
+int main (int argc, const char * argv[]) 
+{
+       /* The behavior of mkdir is undefined for anything other than the "permission" bits */
+       if (mkdir("/tmp/blah", 0777))
+               perror("/tmp/blah");    
+
+       /* So we need to set the sticky/executable bits explicitly with chmod after calling mkdir */
+       if (chmod("/tmp/blah", 07777))
+               perror("/tmp/blah");    
+}
+
+.Ed 
 .Sh LEGACY SYNOPSIS
 .Fd #include <sys/types.h>
 .Fd #include <sys/stat.h>
@@ -144,3 +221,10 @@ The
 .Fn mkdir
 function conforms to 
 .St -p1003.1-88 .
+The
+.Fn mkdirat
+system call is expected to conform to POSIX.1-2008 .
+.Sh HISTORY
+The
+.Fn mkdirat
+system call appeared in OS X 10.10