/share/man/man9/accf_data.9

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    2. 

  2. .\" Copyright (c) 2000 Alfred Perlstein
    3. 

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  27. .\" "
    28. 

  28. .Dd November 15, 2000
    29. 

  29. .Dt ACCF_DATA 9
    30. 

  30. .Os
    31. 

  31. .Sh NAME
    32. 

  32. .Nm accf_data
    33. 

  33. .Nd buffer incoming connections until data arrives
    34. 

  34. .Sh SYNOPSIS
    35. 

  35. .Nm options INET
    36. 

  36. .Nm options ACCEPT_FILTER_DATA
    37. 

  37. .Nm kldload accf_data
    38. 

  38. .Sh DESCRIPTION
    39. 

  39. This is a filter to be placed on a socket that will be using
    40. 

  40. .Fn accept
    41. 

  41. to receive incoming connections.
    42. 

  42. .Pp
    43. 

  43. It prevents the application from receiving the connected descriptor via
    44. 

  44. .Fn accept
    45. 

  45. until data arrives on the connection.
    46. 

  46. .Pp
    47. 

  47. The
    48. 

  48. .Fa ACCEPT_FILTER_DATA
    49. 

  49. kernel option is also a module that can be enabled at runtime via
    50. 

  50. .Xr kldload 8
    51. 

  51. if the INET option has been compiled into the kernel.
    52. 

  52. .Sh EXAMPLES
    53. 

  53. Assuming ACCEPT_FILTER_DATA has been included in the kernel config
    54. 

  54. file or the
    55. 

  55. .Nm
    56. 

  56. module
    57. 

  57. has been loaded, this will enable the data accept filter
    58. 

  58. on the socket
    59. 

  59. .Fa sok .
    60. 

  60. .Bd -literal -offset 0i
    61. 

  61. 	struct accept_filter_arg afa;
    62. 

  62. 

  63. 	bzero(&afa, sizeof(afa));
    64. 

  64. 	strcpy(afa.af_name, "dataready");
    65. 

  65. 	setsockopt(sok, SOL_SOCKET, SO_ACCEPTFILTER, &afa, sizeof(afa));
    66. 

  66. .Ed
    67. 

  67. .Sh SEE ALSO
    68. 

  68. .Xr setsockopt 2 ,
    69. 

  69. .Xr accept_filter 9 ,
    70. 

  70. .Xr accf_dns 9
    71. 

  71. .Xr accf_http 9
    72. 

  72. .Sh HISTORY
    73. 

  73. The accept filter mechanism and the
    74. 

  74. accf_data filter were introduced in
    75. 

  75. .Fx 4.0 .
    76. 

  76. .Sh AUTHORS
    77. 

  77. This manual page and the filter were written by
    78. 

  78. .An Alfred Perlstein .
    79.