ioctl(2) [opensolaris man page]
ioctl(2) System Calls ioctl(2) NAME
ioctl - control device SYNOPSIS
#include <unistd.h> #include <stropts.h> int ioctl(int fildes, int request, /* arg */ ...); DESCRIPTION
The ioctl() function performs a variety of control functions on devices and STREAMS. For non-STREAMS files, the functions performed by this call are device-specific control functions. The request argument and an optional third argument with varying type are passed to the file designated by fildes and are interpreted by the device driver. For STREAMS files, specific functions are performed by the ioctl() function as described in streamio(7I). The fildes argument is an open file descriptor that refers to a device. The request argument selects the control function to be performed and depends on the device being addressed. The arg argument represents a third argument that has additional information that is needed by this specific device to perform the requested function. The data type of arg depends upon the particular control request, but it is either an int or a pointer to a device-specific data structure. In addition to device-specific and STREAMS functions, generic functions are provided by more than one device driver (for example, the gen- eral terminal interface.) See termio(7I)). RETURN VALUES
Upon successful completion, the value returned depends upon the device control function, but must be a non-negative integer. Otherwise, -1 is returned and errno is set to indicate the error. ERRORS
The ioctl() function will fail for any type of file if: EBADF The fildes argument is not a valid open file descriptor. EINTR A signal was caught during the execution of the ioctl() function. EINVAL The STREAM or multiplexer referenced by fildes is linked (directly or indirectly) downstream from a multiplexer. The ioctl() function will also fail if the device driver detects an error. In this case, the error is passed through ioctl() without change to the caller. A particular driver might not have all of the following error cases. Under the following conditions, requests to device drivers may fail and set errno to indicate the error EFAULT The request argument requires a data transfer to or from a buffer pointed to by arg, but arg points to an illegal address. EINVAL The request or arg argument is not valid for this device. EIO Some physical I/O error has occurred. ENOLINK The fildes argument is on a remote machine and the link to that machine is no longer active. ENOTTY The fildes argument is not associated with a STREAMS device that accepts control functions. ENXIO The request and arg arguments are valid for this device driver, but the service requested can not be performed on this particu- lar subdevice. ENODEV The fildes argument refers to a valid STREAMS device, but the corresponding device driver does not support the ioctl() function. STREAMS errors are described in streamio(7I). ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
attributes(5), standards(5), streamio(7I), termio(7I) SunOS 5.11 15 Feb 1996 ioctl(2)
Check Out this Related Man Page
sad(7D) Devices sad(7D) NAME
sad - STREAMS Administrative Driver SYNOPSIS
#include <sys/types.h> #include <sys/conf.h> #include <sys/sad.h> #include <sys/stropts.h> int ioctl(int fildes, int command, int arg); 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 using /dev/sad/admin. Unprivileged operations may access the sad driver using /dev/sad/user. The fildes argument is an open file descriptor that refers to the sad driver. The command argument determines the control function to be performed as described below. The arg argument 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 following commands: SAD_SAP Allows the administrator to configure the given device's autopush information. arg points to a strapush structure, which con- tains the following members: unit_t ap_cmd; major_t sap_major; minor_t sap_minor; minor_t sap_lastminor; unit_t sap_npush; unit_t sap_list [MAXAPUSH] [FMNAMESZ + 1]; The sap_cmd field indicates the type of configuration being done. It may take on one of the following values: SAP_ONE Configure one minor device of a driver. SAP_RANGE Configure a range of minor devices of a driver. SAP_ALL Configure all minor devices of a driver. SAP_CLEAR Undo configuration information for a driver. The sap_major field is the major device number of the device to be configured. The sap_minor field is the minor device number of the device to be configured. The sap_lastminor field is used only with the SAP_RANGE command, which configures a range of minor devices between sap_minor and sap_lastminor, inclusive. The minor fields have no meaning for the SAP_ALL command. The sap_npush 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 sap_list is an array of NULL-terminated module names to be pushed in the order in which they appear in the list. When using the SAP_CLEAR command, the user sets only sap_major and sap_minor. This will undo the configuration information for any of the other commands. If a previous entry was configured as SAP_ALL, sap_minor should be set to zero. If a previous entry was configured as SAP_RANGE , sap_minor 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 SAP_RANGE and sap_lastminor is not greater than sap_minor, or the command is SAP_CLEAR and sap_minor is not equal to the first minor in the range. ENODEV The command is SAP_CLEAR and the device is not configured for autopush. ENOSR An internal autopush data structure cannot be allocated. SAD_GAP 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. The user should set the sap_major and sap_minor 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. SAD_VML Allows any user to validate a list of modules (that is, to see if they are installed on the system). arg is a pointer to a str_list structure with the following members: int sl_nmods; struct str_mlist *sl_modlist; The str_mlist structure has the following member: char l_name[FMNAMESZ+1]; sl_nmods indicates the number of entries the user has allocated in the array and sl_modlist 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 sl_nmods field of the str_list structure is less than or equal to zero. SEE ALSO
Intro(2), ioctl(2), open(2) STREAMS Programming Guide DIAGNOSTICS
Unless otherwise specified, the return value from ioctl() is 0 upon success and -1 upon failure with errno set as indicated. SunOS 5.11 16 Apr 1997 sad(7D)