sad(7) UNIX System V sad(7)
NAME
sad - STREAMS Administrative Driver
SYNOPSIS
#include <sys/types.h>
#include <sys/conf.h>
#include <sys/sad.h>
#include <sys/stropts.h>
int ioctl (fildes, command, arg);
int fildes, command;
DESCRIPTION
The STREAMS Administrative Driver provides an interface for applications
to perform administrative operations on STREAMS modules and drivers. The
interface is provided through ioctl(2) commands. Privileged operations
may access the sad driver via /dev/sad/admin. Unprivileged operations
may access the sad driver via /dev/sad/user.
fildes is an open file descriptor that refers to the sad driver. command
determines the control function to be performed as described below. arg
represents additional information that is needed by this command. The
type of arg depends upon the command, but it is generally an integer or a
pointer to a command-specific data structure.
COMMAND FUNCTIONS
The autopush facility [see autopush(1M)] allows one to configure a list
of modules to be automatically pushed on a stream when a driver is first
opened. Autopush is controlled by the next commands.
SADSAP Allows the administrator to configure the autopush
information for the given device. arg points to a strapush
structure which contains the following members:
uint sapcmd;
long sapmajor;
long sapminor;
long saplastminor;
long sapnpush;
uint saplist[MAXAPUSH] [FMNAMESZ + 1];
The sapcmd field indicates the type of configuration being
done. It may take on one of the following values:
SAPONE Configure one minor device of a driver.
SAPRANGE Configure a range of minor devices of a driver.
SAPALL Configure all minor devices of a driver.
SAPCLEAR Undo configuration information for a driver.
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sad(7) UNIX System V sad(7)
The sapmajor field is the major device number of the device
to be configured. The sapminor field is the minor device
number of the device to be configured. The saplastminor
field is used only with the SAPRANGE command, with which a
range of minor devices between sapminor and saplastminor,
inclusive, are to be configured. The minor fields have no
meaning for the SAPALL command. The sapnpush field
indicates the number of modules to be automatically pushed
when the device is opened. It must be less than or equal to
MAXAPUSH, defined in sad.h. It must also be less than or
equal to NSTRPUSH, the maximum number of modules that can be
pushed on a stream, defined in the kernel master file. The
field saplist is an array of module names to be pushed in
the order in which they appear in the list.
When using the SAPCLEAR command, the user sets only
sapmajor and sapminor. This will undo the configuration
information for any of the other commands. If a previous
entry was configured as SAPALL, sapminor should be set to
zero. If a previous entry was configured as SAPRANGE,
sapminor should be set to the lowest minor device number in
the range configured.
On failure, errno is set to the following value:
EFAULT arg points outside the allocated address space.
EINVAL The major device number is invalid, the number
of modules is invalid, or the list of module
names is invalid.
ENOSTR The major device number does not represent a
STREAMS driver.
EEXIST The major-minor device pair is already
configured.
ERANGE The command is SAPRANGE and saplastminor is
not greater than sapminor, or the command is
SAPCLEAR and sapminor is not equal to the
first minor in the range.
ENODEV The command is SAPCLEAR and the device is not
configured for autopush.
ENOSR An internal autopush data structure cannot be
allocated.
SADGAP Allows any user to query the sad driver to get the autopush
configuration information for a given device. arg points to
a strapush structure as described in the previous command.
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sad(7) UNIX System V sad(7)
The user should set the sapmajor and sapminor fields of
the strapush structure to the major and minor device
numbers, respectively, of the device in question. On
return, the strapush structure will be filled in with the
entire information used to configure the device. Unused
entries in the module list will be zero-filled.
On failure, errno is set to one of the following values:
EFAULT arg points outside the allocated address space.
EINVAL The major device number is invalid.
ENOSTR The major device number does not represent a
STREAMS driver.
ENODEV The device is not configured for autopush.
SADVML Allows any user to validate a list of modules (such as, to
see if they are installed on the system.) arg is a pointer
to a strlist structure with the following members:
int slnmods;
struct strmlist*slmodlist;
The strmlist structure has the following member:
char lname[FMNAMESZ+1];
slnmods indicates the number of entries the user has
allocated in the array and slmodlist points to the array of
module names. The return value is 0 if the list is valid, 1
if the list contains an invalid module name, or -1 on
failure. On failure, errno is set to one of the following
values:
EFAULT arg points outside the allocated address space.
EINVAL The slnmods field of the strlist structure is
less than or equal to zero.
SEE ALSO
intro(2), ioctl(2), open(2)
Programmer's Guide: STREAMS
DIAGNOSTICS
Unless specified otherwise above, the return value from ioctl is 0 upon
success and -1 upon failure with errno set as indicated.
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