ares_mkquery.3 2.7 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889
  1. .\"
  2. .\" Copyright 1998, 2000 by the Massachusetts Institute of Technology.
  3. .\"
  4. .\" Permission to use, copy, modify, and distribute this
  5. .\" software and its documentation for any purpose and without
  6. .\" fee is hereby granted, provided that the above copyright
  7. .\" notice appear in all copies and that both that copyright
  8. .\" notice and this permission notice appear in supporting
  9. .\" documentation, and that the name of M.I.T. not be used in
  10. .\" advertising or publicity pertaining to distribution of the
  11. .\" software without specific, written prior permission.
  12. .\" M.I.T. makes no representations about the suitability of
  13. .\" this software for any purpose. It is provided "as is"
  14. .\" without express or implied warranty.
  15. .\"
  16. .TH ARES_MKQUERY 3 "20 Nov 2009"
  17. .SH NAME
  18. ares_mkquery \- Compose a single-question DNS query buffer
  19. .SH SYNOPSIS
  20. .nf
  21. #include <ares.h>
  22. int ares_mkquery(const char *\fIname\fP, int \fIdnsclass\fP, int \fItype\fP,
  23. unsigned short \fIid\fP, int \fIrd\fP, unsigned char **\fIbuf\fP,
  24. int *\fIbuflen\fP)
  25. .fi
  26. .SH DESCRIPTION
  27. Deprecated function. See \fIares_create_query(3)\fP instead!
  28. The
  29. .B ares_mkquery
  30. function composes a DNS query with a single question.
  31. The parameter
  32. .I name
  33. gives the query name as a NUL-terminated C string of period-separated
  34. labels optionally ending with a period; periods and backslashes within
  35. a label must be escaped with a backlash. The parameters
  36. .I dnsclass
  37. and
  38. .I type
  39. give the class and type of the query using the values defined in
  40. .BR <arpa/nameser.h> .
  41. The parameter
  42. .I id
  43. gives a 16-bit identifier for the query. The parameter
  44. .I rd
  45. should be nonzero if recursion is desired, zero if not. The query
  46. will be placed in an allocated buffer, a pointer to which will be
  47. stored in the variable pointed to by
  48. .IR buf ,
  49. and the length of which will be stored in the variable pointed to by
  50. .IR buflen .
  51. It is the caller's responsibility to free this buffer using
  52. \fIares_free_string(3)\fP when it is no longer needed.
  53. Usage of \fIares_mkquery(3)\fP is deprecated, whereas the function is
  54. equivalent to \fIares_create_query(3)\fP with \fBmax_udp_size\fP set to
  55. 0.
  56. .SH RETURN VALUES
  57. .B ares_mkquery
  58. can return any of the following values:
  59. .TP 15
  60. .B ARES_SUCCESS
  61. Construction of the DNS query succeeded.
  62. .TP 15
  63. .B ARES_ENOTFOUND
  64. The query name
  65. .I name
  66. refers to a
  67. .I .onion
  68. domain name. See RFC 7686.
  69. .TP 15
  70. .B ARES_EBADNAME
  71. The query name
  72. .I name
  73. could not be encoded as a domain name, either because it contained a
  74. zero-length label or because it contained a label of more than 63
  75. characters.
  76. .TP 15
  77. .B ARES_ENOMEM
  78. Memory was exhausted.
  79. .SH SEE ALSO
  80. .BR ares_expand_name (3),
  81. .BR ares_free_string (3)
  82. .SH AUTHOR
  83. Greg Hudson, MIT Information Systems
  84. .br
  85. Copyright 1998, 2000 by the Massachusetts Institute of Technology.