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diff --git a/plugins/FTPFileYM/curl/docs/libcurl/libcurl.3 b/plugins/FTPFileYM/curl/docs/libcurl/libcurl.3 deleted file mode 100644 index d2dcd78388..0000000000 --- a/plugins/FTPFileYM/curl/docs/libcurl/libcurl.3 +++ /dev/null @@ -1,222 +0,0 @@ -.\" ************************************************************************** -.\" * _ _ ____ _ -.\" * Project ___| | | | _ \| | -.\" * / __| | | | |_) | | -.\" * | (__| |_| | _ <| |___ -.\" * \___|\___/|_| \_\_____| -.\" * -.\" * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al. -.\" * -.\" * This software is licensed as described in the file COPYING, which -.\" * you should have received as part of this distribution. The terms -.\" * are also available at http://curl.haxx.se/docs/copyright.html. -.\" * -.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell -.\" * copies of the Software, and permit persons to whom the Software is -.\" * furnished to do so, under the terms of the COPYING file. -.\" * -.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY -.\" * KIND, either express or implied. -.\" * -.\" ************************************************************************** -.TH libcurl 3 "19 March 2002" "libcurl 7.9.6" "libcurl overview" -.SH NAME -libcurl \- client-side URL transfers -.SH DESCRIPTION -This is a short overview on how to use libcurl in your C programs. There are -specific man pages for each function mentioned in here. There are also the -\fIlibcurl-easy(3)\fP man page, the \fIlibcurl-multi(3)\fP man page, the -\fIlibcurl-share(3)\fP man page and the \fIlibcurl-tutorial(3)\fP man page for -in-depth understanding on how to program with libcurl. - -There are more than thirty custom bindings available that bring libcurl access -to your favourite language. Look elsewhere for documentation on those. - -libcurl has a global constant environment that you must set up and -maintain while using libcurl. This essentially means you call -\fIcurl_global_init(3)\fP at the start of your program and -\fIcurl_global_cleanup(3)\fP at the end. See GLOBAL CONSTANTS below -for details. - -To transfer files, you always set up an "easy handle" using -\fIcurl_easy_init(3)\fP, but when you want the file(s) transferred you have -the option of using the "easy" interface, or the "multi" interface. - -The easy interface is a synchronous interface with which you call -\fIcurl_easy_perform(3)\fP and let it perform the transfer. When it is -completed, the function returns and you can continue. More details are found in -the \fIlibcurl-easy(3)\fP man page. - -The multi interface on the other hand is an asynchronous interface, that you -call and that performs only a little piece of the transfer on each invoke. It -is perfect if you want to do things while the transfer is in progress, or -similar. The multi interface allows you to select() on libcurl action, and -even to easily download multiple files simultaneously using a single thread. See further details in the \fIlibcurl-multi(3)\fP man page. - -You can have multiple easy handles share certain data, even if they are used -in different threads. This magic is setup using the share interface, as -described in the \fIlibcurl-share(3)\fP man page. - -There is also a series of other helpful functions to use, including these: -.RS -.IP curl_version_info() -gets detailed libcurl (and other used libraries) version info -.IP curl_getdate() -converts a date string to time_t -.IP curl_easy_getinfo() -get information about a performed transfer -.IP curl_formadd() -helps building an HTTP form POST -.IP curl_formfree() -free a list built with \fIcurl_formadd(3)\fP -.IP curl_slist_append() -builds a linked list -.IP curl_slist_free_all() -frees a whole curl_slist -.RE - -.SH "LINKING WITH LIBCURL" -On unix-like machines, there's a tool named curl-config that gets installed -with the rest of the curl stuff when 'make install' is performed. - -curl-config is added to make it easier for applications to link with libcurl -and developers to learn about libcurl and how to use it. - -Run 'curl-config --libs' to get the (additional) linker options you need to -link with the particular version of libcurl you've installed. See the -\fIcurl-config(1)\fP man page for further details. - -Unix-like operating system that ship libcurl as part of their distributions -often don't provide the curl-config tool, but simply install the library and -headers in the common path for this purpose. - -.SH "LIBCURL SYMBOL NAMES" -All public functions in the libcurl interface are prefixed with 'curl_' (with -a lowercase c). You can find other functions in the library source code, but -other prefixes indicate that the functions are private and may change without -further notice in the next release. - -Only use documented functions and functionality! -.SH "PORTABILITY" -libcurl works -.B exactly -the same, on any of the platforms it compiles and builds on. -.SH "THREADS" -Never ever call curl-functions simultaneously using the same handle from -several threads. libcurl is thread-safe and can be used in any number of -threads, but you must use separate curl handles if you want to use libcurl in -more than one thread simultaneously. - -The global environment functions are not thread-safe. See GLOBAL CONSTANTS -below for details. - -.SH "PERSISTENT CONNECTIONS" -Persistent connections means that libcurl can re-use the same connection for -several transfers, if the conditions are right. - -libcurl will \fBalways\fP attempt to use persistent connections. Whenever you -use \fIcurl_easy_perform(3)\fP or \fIcurl_multi_perform(3)\fP, libcurl will -attempt to use an existing connection to do the transfer, and if none exists -it'll open a new one that will be subject for re-use on a possible following -call to \fIcurl_easy_perform(3)\fP or \fIcurl_multi_perform(3)\fP. - -To allow libcurl to take full advantage of persistent connections, you should -do as many of your file transfers as possible using the same curl handle. When -you call \fIcurl_easy_cleanup(3)\fP, all the possibly open connections held by -libcurl will be closed and forgotten. - -Note that the options set with \fIcurl_easy_setopt(3)\fP will be used on -every repeated \fIcurl_easy_perform(3)\fP call. - -.SH "GLOBAL CONSTANTS" -There are a variety of constants that libcurl uses, mainly through its -internal use of other libraries, which are too complicated for the -library loader to set up. Therefore, a program must call a library -function after the program is loaded and running to finish setting up -the library code. For example, when libcurl is built for SSL -capability via the GNU TLS library, there is an elaborate tree inside -that library that describes the SSL protocol. - -\fIcurl_global_init()\fP is the function that you must call. This may -allocate resources (e.g. the memory for the GNU TLS tree mentioned -above), so the companion function \fIcurl_global_cleanup()\fP releases -them. - -The basic rule for constructing a program that uses libcurl is this: -Call \fIcurl_global_init()\fP, with a \fICURL_GLOBAL_ALL\fP argument, -immediately after the program starts, while it is still only one -thread and before it uses libcurl at all. Call -\fIcurl_global_cleanup()\fP immediately before the program exits, when -the program is again only one thread and after its last use of -libcurl. - -You can call both of these multiple times, as long as all calls meet -these requirements and the number of calls to each is the same. - -It isn't actually required that the functions be called at the beginning -and end of the program -- that's just usually the easiest way to do it. -It \fIis\fP required that the functions be called when no other thread -in the program is running. - -These global constant functions are \fInot thread safe\fP, so you must -not call them when any other thread in the program is running. It -isn't good enough that no other thread is using libcurl at the time, -because these functions internally call similar functions of other -libraries, and those functions are similarly thread-unsafe. You can't -generally know what these libraries are, or whether other threads are -using them. - -The global constant situation merits special consideration when the -code you are writing to use libcurl is not the main program, but rather -a modular piece of a program, e.g. another library. As a module, -your code doesn't know about other parts of the program -- it doesn't -know whether they use libcurl or not. And its code doesn't necessarily -run at the start and end of the whole program. - -A module like this must have global constant functions of its own, -just like \fIcurl_global_init()\fP and \fIcurl_global_cleanup()\fP. -The module thus has control at the beginning and end of the program -and has a place to call the libcurl functions. Note that if multiple -modules in the program use libcurl, they all will separately call the -libcurl functions, and that's OK because only the first -\fIcurl_global_init()\fP and the last \fIcurl_global_cleanup()\fP in a -program change anything. (libcurl uses a reference count in static -memory). - -In a C++ module, it is common to deal with the global constant -situation by defining a special class that represents the global -constant environment of the module. A program always has exactly one -object of the class, in static storage. That way, the program -automatically calls the constructor of the object as the program -starts up and the destructor as it terminates. As the author of this -libcurl-using module, you can make the constructor call -\fIcurl_global_init()\fP and the destructor call -\fIcurl_global_cleanup()\fP and satisfy libcurl's requirements without -your user having to think about it. - -\fIcurl_global_init()\fP has an argument that tells what particular -parts of the global constant environment to set up. In order to -successfully use any value except \fICURL_GLOBAL_ALL\fP (which says to -set up the whole thing), you must have specific knowledge of internal -workings of libcurl and all other parts of the program of which it is -part. - -A special part of the global constant environment is the identity of -the memory allocator. \fIcurl_global_init()\fP selects the system -default memory allocator, but you can use \fIcurl_global_init_mem()\fP -to supply one of your own. However, there is no way to use -\fIcurl_global_init_mem()\fP in a modular program -- all modules in -the program that might use libcurl would have to agree on one -allocator. - -There is a failsafe in libcurl that makes it usable in simple -situations without you having to worry about the global constant -environment at all: \fIcurl_easy_init()\fP sets up the environment -itself if it hasn't been done yet. The resources it acquires to do so -get released by the operating system automatically when the program -exits. - -This failsafe feature exists mainly for backward compatibility because -there was a time when the global functions didn't exist. Because it -is sufficient only in the simplest of programs, it is not recommended -for any program to rely on it. |