[unix-history] / usr / man / man2 / umask.2

.TH UMASK 2
.SH NAME
umask \- set file creation mode mask
.SH SYNOPSIS
.B umask(complmode)
.SH DESCRIPTION
.I Umask
sets a mask used whenever a file is created by
.IR creat (2)
or
.IR mknod (2):
the actual mode (see
.IR chmod (2))
of the newly-created file is the logical
.B and
of the given mode and the complement of the argument.
Only the low-order 9 bits of the mask (the protection bits)
participate.
In other words, the mask shows the bits to be turned off
when files are created.
.PP
The previous value of the mask is returned by the call.
The value is initially 0 (no restrictions).
The mask is inherited by child processes.
.SH SEE ALSO
creat(2), mknod(2), chmod(2)
.SH "ASSEMBLER (PDP-11)"
(umask = 60.)
.br
.B sys umask; complmode
Commit	Line	Data
e6817382 BJ	1	.TH UMASK 2
	2	.SH NAME
	3	umask \- set file creation mode mask
	4	.SH SYNOPSIS
	5	.B umask(complmode)
	6	.SH DESCRIPTION
	7	.I Umask
	8	sets a mask used whenever a file is created by
	9	.IR creat (2)
	10	or
	11	.IR mknod (2):
	12	the actual mode (see
	13	.IR chmod (2))
	14	of the newly-created file is the logical
	15	.B and
	16	of the given mode and the complement of the argument.
	17	Only the low-order 9 bits of the mask (the protection bits)
	18	participate.
	19	In other words, the mask shows the bits to be turned off
	20	when files are created.
	21	.PP
	22	The previous value of the mask is returned by the call.
	23	The value is initially 0 (no restrictions).
	24	The mask is inherited by child processes.
	25	.SH SEE ALSO
	26	creat(2), mknod(2), chmod(2)
	27	.SH "ASSEMBLER (PDP-11)"
	28	(umask = 60.)
	29	.br
	30	.B sys umask; complmode