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c-ares is a C library for asynchronous DNS requests http://c-ares.haxx.se/
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m4 test: Add framework for containerized testing
test test: Check ares_parse_txt_reply_ext() entrypoint
vc vc6cares.dsp: add ares_create_query.c and ares_parse_soa_reply.c
.gitignore build: Add a code coverage option
.travis.yml test: Run command line tools in Travis
AUTHORS doc: Update in preparation for next release
CHANGES CHANGES: generate from script
CHANGES.0 CHANGES: generate from script
CONTRIBUTING.md doc: Update docs on contributing
GIT-INFO GIT-INFO: mention buildconf
INSTALL INSTALL: some adjustments
Makefile.Watcom
Makefile.am build: Add a code coverage option
Makefile.dj build: config.dos renamed to config-dos.h
Makefile.inc
Makefile.m32 Create ares_build.h when buidling from Git.
Makefile.msvc Support Visual Studio 2015
Makefile.netware Makefile.netware: SIZEOF_SHORT definition
NEWS - Fixed a few variable return types for some system calls. Made confi…
README.cares README.cares: s/I/Daniel
README.md doc: Update missed repo references
README.msvc build: add install target to Makefile.msvc
RELEASE-NOTES doc: Update in preparation for next release
TODO ares_reinit()
acinclude.m4 nowarn: use <limits.h> instead of configure for size of long
acountry.1 man pages: docs for the c-ares utility programs
acountry.c acountry: drop inert test
adig.1 man pages: docs for the c-ares utility programs
adig.c ares_inet_pton/ntop: cleanup
ahost.1 Add -t u option to ahost
ahost.c ahost: Allow repeated -s <domain> options
appveyor.yml test: Get test code building under Windows
ares.h txt: introduce `ares_parse_txt_reply_ext`
ares__close_sockets.c api: Allow injection of user-specified malloc/free functions
ares__get_hostent.c api: Allow injection of user-specified malloc/free functions
ares__read_line.c api: Allow injection of user-specified malloc/free functions
ares__timeval.c
ares_build.h.dist ares_build.h: fix building on 64-bit powerpc
ares_build.h.in Revert "Do not use sized constants in public headers"
ares_cancel.3 Documentation: properly document ARES_ECANCELLED
ares_cancel.c ares_cancel(): cancel requests safely
ares_create_query.3
ares_create_query.c api: Allow injection of user-specified malloc/free functions
ares_data.c txt: introduce `ares_parse_txt_reply_ext`
ares_data.h txt: introduce `ares_parse_txt_reply_ext`
ares_destroy.3 ares_destroy() documentation: no new requests
ares_destroy.c api: Allow injection of user-specified malloc/free functions
ares_destroy_options.3 remove all $Id$ lines
ares_dns.h Added new feature (rfc2671)
ares_dup.3 remove all $Id$ lines
ares_expand_name.3 ares_expand_name.3: clarify how to free the data
ares_expand_name.c api: Allow injection of user-specified malloc/free functions
ares_expand_string.3 remove all $Id$ lines
ares_expand_string.c api: Allow injection of user-specified malloc/free functions
ares_fds.3 remove all $Id$ lines
ares_fds.c Header inclusion clean-up
ares_free_data.3 SOA parser added
ares_free_hostent.3 remove all $Id$ lines
ares_free_hostent.c api: Allow injection of user-specified malloc/free functions
ares_free_string.3
ares_free_string.c api: Allow injection of user-specified malloc/free functions
ares_get_servers.3 api: Add entrypoints to allow use of per-server ports
ares_get_servers_ports.3 api: Add entrypoints to allow use of per-server ports
ares_getenv.c build: use getenv() replacement function for systems which lack it
ares_getenv.h build: use getenv() replacement function for systems which lack it
ares_gethostbyaddr.3 Documentation: properly document ARES_ECANCELLED
ares_gethostbyaddr.c api: Allow injection of user-specified malloc/free functions
ares_gethostbyname.3 Documentation: properly document ARES_ECANCELLED
ares_gethostbyname.c api: Allow injection of user-specified malloc/free functions
ares_gethostbyname_file.3 remove all $Id$ lines
ares_getnameinfo.3 ares_getnameinfo.3: there is no ares_getaddrinfo
ares_getnameinfo.c api: Allow injection of user-specified malloc/free functions
ares_getopt.c remove all $Id$ lines
ares_getopt.h Fix macro redefinition.
ares_getsock.3 remove all $Id$ lines
ares_getsock.c Fix integer shift overflow if both tcp_socket and udp_socket are set
ares_inet_net_pton.h ares_inet_pton/ntop: cleanup
ares_inet_ntop.3 ares_inet_ntop.3: s/socklen_t/ares_socklen_t
ares_inet_pton.3 spell inet correctly!
ares_init.3 Fix typos detected by lintian
ares_init.c api: Add entrypoints to allow use of per-server ports
ares_init_options.3 remove all $Id$ lines
ares_iphlpapi.h ares_iphlpapi.h: Watcom C fix
ares_ipv6.h Comment in ares_ipv6.h
ares_library_cleanup.3 library init: documentation update
ares_library_init.3 api: Allow injection of user-specified malloc/free functions
ares_library_init.c api: Allow injection of user-specified malloc/free functions
ares_library_init.h winsock: compilation fixes
ares_llist.c ares__swap_lists: make private and static
ares_llist.h ares__swap_lists: make private and static
ares_mkquery.3 Added new feature (rfc2671)
ares_mkquery.c Added new feature (rfc2671)
ares_nowarn.c nowarn: use <limits.h> instead of configure for size of long
ares_nowarn.h Kill compiler warning
ares_options.c api: Add entrypoints to allow use of per-server ports
ares_parse_a_reply.3 nroff: fix two syntax mistakes
ares_parse_a_reply.c api: Allow injection of user-specified malloc/free functions
ares_parse_aaaa_reply.3 nroff: fix two syntax mistakes
ares_parse_aaaa_reply.c
ares_parse_mx_reply.3 added ares_parse_mx_reply
ares_parse_mx_reply.c
ares_parse_naptr_reply.3 Added support for parsing NAPTR records
ares_parse_naptr_reply.c api: Allow injection of user-specified malloc/free functions
ares_parse_ns_reply.3 Vlad Dinulescu added ares_parse_ns_reply()
ares_parse_ns_reply.c api: Allow injection of user-specified malloc/free functions
ares_parse_ptr_reply.3 remove all $Id$ lines
ares_parse_ptr_reply.c api: Allow injection of user-specified malloc/free functions
ares_parse_soa_reply.3 SOA parser added
ares_parse_soa_reply.c api: Allow injection of user-specified malloc/free functions
ares_parse_srv_reply.3 Daniel wants upcoming release to be 1.7.0
ares_parse_srv_reply.c api: Allow injection of user-specified malloc/free functions
ares_parse_txt_reply.3 txt: introduce `ares_parse_txt_reply_ext`
ares_parse_txt_reply.c txt: introduce `ares_parse_txt_reply_ext`
ares_platform.c compiler warning: fix
ares_platform.h getservbyport replacement for Win CE
ares_private.h api: Add entrypoints to allow use of per-server ports
ares_process.3 remove all $Id$ lines
ares_process.c api: Add entrypoints to allow use of per-server ports
ares_query.3
ares_query.c api: Allow injection of user-specified malloc/free functions
ares_rules.h ares_rules.h: CARES_SIZEOF_LONG doesn't exist anymore, don't test for it
ares_save_options.3 remove all $Id$ lines
ares_search.3 Documentation: properly document ARES_ECANCELLED
ares_search.c
ares_send.3 Documentation: properly document ARES_ECANCELLED
ares_send.c api: Allow injection of user-specified malloc/free functions
ares_set_local_dev.3 Fix typos detected by lintian
ares_set_local_ip4.3 ares_set_local_*: added in 1.7.4, not before
ares_set_local_ip6.3 ares_set_local_*: added in 1.7.4, not before
ares_set_servers.3 api: Add entrypoints to allow use of per-server ports
ares_set_servers_csv.3 api: Add entrypoints to allow use of per-server ports
ares_set_servers_ports.3 api: Add entrypoints to allow use of per-server ports
ares_set_servers_ports_csv.3 api: Add entrypoints to allow use of per-server ports
ares_set_socket_callback.3 remove all $Id$ lines
ares_set_sortlist.3 api: Add ares_set_sortlist(3) entrypoint
ares_setup.h Check for __ANDROID__ in addition to ANDROID macro.
ares_strcasecmp.c remove all $Id$ lines
ares_strcasecmp.h remove all $Id$ lines
ares_strdup.c api: Allow injection of user-specified malloc/free functions
ares_strdup.h api: Allow injection of user-specified malloc/free functions
ares_strerror.3 remove all $Id$ lines
ares_strerror.c remove all $Id$ lines
ares_timeout.3 ares_timeout.3: fix the NAME section
ares_timeout.c timeoffset: made static and private
ares_version.3 remove all $Id$ lines
ares_version.c remove all $Id$ lines
ares_version.h bump: start working towards 1.10.1
ares_writev.c api: Allow injection of user-specified malloc/free functions
ares_writev.h remove all $Id$ lines
bitncmp.c bitncmp: update comment to match code behaviour
bitncmp.h ares__bitncmp: use two underscores for private functions
buildconf Fix buildconf on platforms using glibtoolize
buildconf.bat remove all $Id$ lines
cares.rc Added copyright string to ares_version.h and make use of it in other …
config-dos.h config-dos.h: define HAVE_CLOSE_S for MSDOS/Watt-32
config-win32.h build: Allow header compilation by Windows C++ compiler
configure.ac build: Add a code coverage option
get_ver.awk Cleaned up version awk script.
git2changes.pl CHANGES: generate from script
inet_net_pton.c Mark unhittable lines
inet_ntop.c inet_ntop.c: s/socklen_t/ares_socklen_t
install-sh refresh: updated now with automake 1.14
libcares.pc.in Fix libcares.pc generation for static MingW* cross builds
maketgz CHANGES: generate from script
mkinstalldirs refresh: updated now with automake 1.14
nameser.h c-ares/nameser.h: add some T_* defines for ns_t_* values
setup_once.h curl_setup_once.h: definition of HAVE_CLOSE_S defines sclose() to clo…
windows_port.c build: move platform stuff to ares_platform.c and ares_platform.h

README.md

c-ares

Build Status Windows Build Status Coverage Status

This is c-ares, an asynchronous resolver library. It is intended for applications which need to perform DNS queries without blocking, or need to perform multiple DNS queries in parallel. The primary examples of such applications are servers which communicate with multiple clients and programs with graphical user interfaces.

The full source code is available in the 'c-ares' release archives, and in a git repository: http://github.com/c-ares/c-ares

If you find bugs, correct flaws, have questions or have comments in general in regard to c-ares (or by all means the original ares too), get in touch with us on the c-ares mailing list: http://cool.haxx.se/mailman/listinfo/c-ares

c-ares is of course distributed under the same MIT-style license as the original ares.

You'll find all c-ares details and news here: http://c-ares.haxx.se/

Notes for c-ares hackers

  • The distributed ares_build.h file is only intended to be used on systems which can not run the also distributed configure script.

  • The distributed ares_build.h file is generated as a copy of ares_build.h.dist when the c-ares source code distribution archive file is originally created.

  • If you check out from git on a non-configure platform, you must run the appropriate buildconf* script to set up ares_build.h and other local files before being able to compile the library.

  • On systems capable of running the configure script, the configure process will overwrite the distributed ares_build.h file with one that is suitable and specific to the library being configured and built, this new file is generated from the ares_build.h.in template file.

  • If you intend to distribute an already compiled c-ares library you MUST also distribute along with it the generated ares_build.h which has been used to compile it. Otherwise the library will be of no use for the users of the library that you have built. It is your responsibility to provide this file. No one at the c-ares project can know how you have built the library.

  • File ares_build.h includes platform and configuration dependent info, and must not be modified by anyone. Configure script generates it for you.

  • We cannot assume anything else but very basic compiler features being present. While c-ares requires an ANSI C compiler to build, some of the earlier ANSI compilers clearly can't deal with some preprocessor operators.

  • Newlines must remain unix-style for older compilers' sake.

  • Comments must be written in the old-style /* unnested C-fashion */

  • Try to keep line lengths below 80 columns.

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