.TH splbase() "" "" "DDI/DKI Kernel Routine"
.PC "Block no interrupts"
.B "#include <sys/inline.h>"
\fBpl_t splbase();\fR
.PP
The functions with the prefix
.B spl
set the level of interrupt priority.
The level assigned depends upon the type of device in question.
.PP
Each
.B spl
function blocks interrupts at or below its level.
The following gives the order of the levels set by the
.B spl
functions:
.DS
	splbase() <= spltimeout() <= spldisk(),splstr() <= splhi()
.DE
.PP
\*(ST does not define how
.B spldisk()
and
.B splstr()
relate to each other.
.PP
.B splbase()
sets the interrupt priority to its lowest level, i.e., it blocks no interrupts.
It returns the previous priority level.
.SH "See Also"
.B
DDI/DKI kernel routines,
spldisk(),
splhi(),
splstr(),
spltimeout()
.R
.SH Notes
.B splbase()
has base or interrupt level.
It does not sleep.
.PP
A driver can hold a
driver-defined basic locks or read/write lock across a call to this function;
however, the call to
.B splbase()
must not lower the interrupt priority below that associated with the lock.
A driver can hold a driver-defined sleep lock across a call to this function.
