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devsw_del(9r)
NAME
  devsw_del - General: Clears entry points from the device switch table

SYNOPSIS
  #include <sys/conf.h>


  int devsw_del(
	  char *driver_name,
	  int driver_reg_instance );

ARGUMENTS
  driver_name
      Specifies a null-terminated string that represents the name of the
      device driver whose I/O services interfaces you want to clear from the
      device switch table. You specified this name in a previous call to the
      devsw_add interface. The driver name must be at least two characters in
      length not to exceed DEVSW_NAME_LEN characters, including the null
      terminator. This name is a string that matches the string you specified
      for the entry_name item in the /etc/sysconfigtab database. Typically,
      third-party driver writers specify the driver name (followed by a
      colon) in the sysconfigtab file fragment, which gets appended to the
      /etc/sysconfigtab database during the driver product installation.

  driver_reg_instance
      Specifies an integer that represents a specific reservation instance
      for this driver. This argument allows a driver to uniquely identify
      multiple major numbers for the driver. This is the integer you passed
      to the driver_reg_instance argument in a previous call to the devsw_add
      interface.

DESCRIPTION
  The devsw_del interface clears a device driver's I/O services interfaces
  (and other information) from the device switch table.	 The interface
  continues to reserve the major number associated with the device driver.

  The devsw_del interface performs appropriate checks on the value passed to
  the driver_name argument.

NOTES
  A device driver calls devsw_del to remove access to its associated I/O
  services interfaces but retain use of its reserved major number. For
  example, a device driver about to be unloaded might want to call devsw_del.






EXAMPLE
  See Writing Device Drivers: Tutorial for a code example of the devsw_del
  interface.


RETURN VALUES
  Upon successful completion, the devsw_del interface returns the major
  number associated with the device driver whose I/O services interfaces were
  cleared from the device switch table. Otherwise, on an error, the devsw_del
  interface returns the value -1. The following list describes possible error
  conditions:

    ·  The devsw_del interface is not available to be called at this point in
       the driver.

    ·  The name you passed to the driver_name argument is not a valid name.

    ·  There is no device switch entry associated with this driver.

SEE ALSO
  Kernel Interfaces: devsw_add(9r), devsw_get(9r)

  Data Structures: dsent(9s)

Index for Section 9

Alphabetical listing for D

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