4.16 My HTTP POST or PUT requests are slow!
4.17 Non-functional connect timeouts on Windows
4.18 file:// URLs containing drive letters (Windows, NetWare)
- 4.19 Why doesn't cURL return an error when the network cable is unplugged?
+ 4.19 Why doesn't curl return an error when the network cable is unplugged?
4.20 curl doesn't return error for HTTP non-200 responses!
4.21 Why is there a HTTP/1.1 in my HTTP/2 request?
another tool that uses libcurl.
We do not add things to curl that other small and available tools already do
- very fine at the side. Curl's output is fine to pipe into another program or
- redirect to another file for the next program to interpret.
+ very well at the side. Curl's output can be piped into another program or
+ redirected to another file for the next program to interpret.
We focus on protocol related issues and improvements. If you wanna do more
- magic with the supported protocols than curl currently does, chances are big
+ magic with the supported protocols than curl currently does, chances are good
we will agree. If you wanna add more protocols, we may very well agree.
- If you want someone else to make all the work while you wait for us to
+ If you want someone else to do all the work while you wait for us to
implement it for you, that is not a very friendly attitude. We spend a
considerable time already on maintaining and developing curl. In order to
get more out of us, you should consider trading in some of your time and
- efforts in return. Simply go to the GitHub repo which resides at
+ effort in return. Simply go to the GitHub repo which resides at
https://github.com/curl/curl, fork the project, and create pull requests
with your proposed changes.
- If you write the code, chances are bigger that it will get into curl faster.
+ If you write the code, chances are better that it will get into curl faster.
1.5 Who makes curl?
project leader and main developer, but other persons' submissions are
important and crucial. Anyone can contribute and post their changes and
improvements and have them inserted in the main sources (of course on the
- condition that developers agree on that the fixes are good).
+ condition that developers agree that the fixes are good).
The full list of all contributors is found in the docs/THANKS file.
1.6 What do you get for making curl?
Project cURL is entirely free and open. No person gets paid for developing
- curl on full time. We do this voluntarily, mostly on spare time.
+ curl full time. We do this voluntarily, mostly in our spare time.
Occasionally companies pay individual developers to work on curl, but that's
- up to each company and developer. It is not controlled by nor supervised in
+ up to each company and developer. This is not controlled by nor supervised in
any way by the project.
We still get help from companies. Haxx provides web site, bandwidth, mailing
do so in the future.
If you want to support our project, consider a donation or a banner-program
- or even better: by helping us coding, documenting, testing etc.
+ or even better: by helping us with coding, documenting or testing etc.
1.7 What about CURL from curl.com?
- During the summer 2001, curl.com was busy advertising their client-side
+ During the summer of 2001, curl.com was busy advertising their client-side
programming language for the web, named CURL.
We are in no way associated with curl.com or their CURL programming
We recognize that we will be living in parallel with curl.com and wish them
every success.
- 1.8 I have a problem who do I mail?
+ 1.8 I have a problem whom do I mail?
Please do not mail any single individual unless you really need to. Keep
curl-related questions on a suitable mailing list. All available mailing
https://curl.haxx.se/mail/
Keeping curl-related questions and discussions on mailing lists allows
- others to join in and help, to share their ideas, contribute their
- suggestions and spread their wisdom. Keeping discussions on public mailing
+ others to join in and help, to share their ideas, to contribute their
+ suggestions and to spread their wisdom. Keeping discussions on public mailing
lists also allows for others to learn from this (both current and future
users thanks to the web based archives of the mailing lists), thus saving us
from having to repeat ourselves even more. Thanks for respecting this.
1.11 Why don't you update ca-bundle.crt
- The ca cert bundle that used to shipped with curl was very outdated and must
- be replaced with an up-to-date version by anyone who wants to verify
- peers. It is no longer provided by curl. The last curl release ever that
+ The ca cert bundle that used to be shipped with curl was very outdated and
+ must be replaced with an up-to-date version by anyone who wants to verify
+ peers. It is no longer provided by curl. The last curl release that ever
shipped a ca cert bundle was curl 7.18.0.
In the cURL project we've decided not to attempt to keep this file updated
1.12 I have a problem who can I chat with?
There's a bunch of friendly people hanging out in the #curl channel on the
- IRC network irc.freenode.net. If you're polite and nice, chances are big
+ IRC network irc.freenode.net. If you're polite and nice, chances are good
that you can get -- or provide -- help instantly.
1.13 curl's ECCN number?
2.1.2 only the libssl lib is missing
If all include files and the libcrypto lib is present, with only the
- libssl being missing according to configure, this is mostly likely because
+ libssl being missing according to configure, this is most likely because
a few functions are left out from the libssl.
If the function names missing include RSA or RSAREF you can be certain
2.5 Install libcurl for both 32bit and 64bit?
- In curl's configure procedure one of the regular include files get created
+ In curl's configure procedure one of the regular include files gets created
with platform specific information. The file 'curl/curlbuild.h' in the
installed libcurl file tree is therefore somewhat tied to that particular
platform.
3.3 Why doesn't my posting using -F work?
- You can't simply use -F or -d at your choice. The web server that will
- receive your post expects one of the formats. If the form you're trying to
- submit uses the type 'multipart/form-data', then and only then you must use
- the -F type. In all the most common cases, you should use -d which then
- causes a posting with the type 'application/x-www-form-urlencoded'.
+ You can't arbitrarily use -F or -d, the choice between -F or -d depends on the
+ HTTP operation you need curl to do and what the web server that will receive
+ your post expects.
+
+ If the form you're trying to submit uses the type 'multipart/form-data', then
+ and only then you must use the -F type. In all the most common cases, you
+ should use -d which then causes a posting with the type
+ 'application/x-www-form-urlencoded'.
This is described in some detail in the MANUAL and TheArtOfHttpScripting
documents, and if you don't understand it the first time, read it again
XML-RPC are all such ones. You can use -X to set custom requests and -H to
set custom headers (or replace internally generated ones).
- Using libcurl is of course just as fine and you'd just use the proper
+ Using libcurl is of course just as good and you'd just use the proper
library options to do the same.
3.11 How do I POST with a different Content-Type?
There is one exception to this rule, and that is if you can "tunnel through"
the given HTTP proxy. Proxy tunneling is enabled with a special option (-p)
and is generally not available as proxy admins usually disable tunneling to
- other ports than 443 (which is used for HTTPS access through proxies).
+ ports other than 443 (which is used for HTTPS access through proxies).
3.13 Why does my single/double quotes fail?
Windows/DOS prompts I believe you're forced to use double (") quotes.
Please study the documentation for your particular environment. Examples in
- the curl docs will use a mix of both these ones as shown above. You must
+ the curl docs will use a mix of both of these as shown above. You must
adjust them to work in your environment.
Remember that curl works and runs on more operating systems than most single
No. curl itself has no code that performs recursive operations, such as
those performed by wget and similar tools.
- There exist wrapper scripts with that functionality (for example the
+ There exists wrapper scripts with that functionality (for example the
curlmirror perl script), and you can write programs based on libcurl to do
it, but the command line tool curl itself cannot.
CLIENT CERTIFICATE
- The server you communicate may require that you can provide this in order to
- prove that you actually are who you claim to be. If the server doesn't
- require this, you don't need a client certificate.
+ The server you communicate with may require that you can provide this in
+ order to prove that you actually are who you claim to be. If the server
+ doesn't require this, you don't need a client certificate.
A client certificate is always used together with a private key, and the
private key has a pass phrase that protects it.
4.3 How can I use {, }, [ or ] to specify multiple URLs?
- Because those letters have a special meaning to the shell, and to be used in
+ Because those letters have a special meaning to the shell, to be used in
a URL specified to curl you must quote them.
- An example that downloads two URLs (sequentially) would do:
+ An example that downloads two URLs (sequentially) would be:
curl '{curl,www}.haxx.se'
- To be able to use those letters as actual parts of the URL (without using
+ To be able to use those characters as actual parts of the URL (without using
them for the curl URL "globbing" system), use the -g/--globoff option:
curl -g 'www.site.com/weirdname[].html'
4.13 Why is curl -R on Windows one hour off?
- During daylight savings time, when -R is used, curl will set a time that
- appears one hour off. This happens due to a flaw in how Windows stores and
- uses file modification times and it is not easily worked around. For details
- on this problem, read this: http://www.codeproject.com/datetime/dstbugs.asp
+ Since curl 7.53.0 this issue should be fixed as long as curl was built with
+ any modern compiler that allows for a 64-bit curl_off_t type. For older
+ compilers or prior curl versions it may set a time that appears one hour off.
+ This happens due to a flaw in how Windows stores and uses file modification
+ times and it is not easily worked around. For more details read this:
+ http://www.codeproject.com/datetime/dstbugs.asp
4.14 Redirects work in browser but not with curl!
- curl supports HTTP redirects fine (see item 3.8). Browsers generally support
+ curl supports HTTP redirects well (see item 3.8). Browsers generally support
at least two other ways to perform redirects that curl does not:
Meta tags. You can write a HTML tag that will cause the browser to redirect
To use explicit FTPS, you use a FTP:// URL and the --ftp-ssl option (or one
of its related flavours). This is the most common method, and the one
- mandated by RFC4217. This kind of connection then of course uses the
+ mandated by RFC4217. This kind of connection will then of course use the
standard FTP port 21 by default.
4.16 My HTTP POST or PUT requests are slow!
libcurl makes all POST and PUT requests (except for POST requests with a
very tiny request body) use the "Expect: 100-continue" header. This header
allows the server to deny the operation early so that libcurl can bail out
- already before having to send any data. This is useful in authentication
+ before having to send any data. This is useful in authentication
cases and others.
However, many servers don't implement the Expect: stuff properly and if the
4.18 file:// URLs containing drive letters (Windows, NetWare)
- When using cURL to try to download a local file, one might use a URL
+ When using curl to try to download a local file, one might use a URL
in this format:
file://D:/blah.txt
- You'll find that even if D:\blah.txt does exist, cURL returns a 'file
+ You'll find that even if D:\blah.txt does exist, curl returns a 'file
not found' error.
According to RFC 1738 (https://www.ietf.org/rfc/rfc1738.txt),
file:// URLs must contain a host component, but it is ignored by
most implementations. In the above example, 'D:' is treated as the
- host component, and is taken away. Thus, cURL tries to open '/blah.txt'.
+ host component, and is taken away. Thus, curl tries to open '/blah.txt'.
If your system is installed to drive C:, that will resolve to 'C:\blah.txt',
and if that doesn't exist you will get the not found error.
file://localhost/D:/blah.txt
- In either case, cURL should now be looking for the correct file.
+ In either case, curl should now be looking for the correct file.
- 4.19 Why doesn't cURL return an error when the network cable is unplugged?
+ 4.19 Why doesn't curl return an error when the network cable is unplugged?
Unplugging a cable is not an error situation. The TCP/IP protocol stack
was designed to be fault tolerant, so even though there may be a physical
When doing HTTP transfers, curl will perform exactly what you're asking it
to do and if successful it will not return an error. You can use curl to
test your web server's "file not found" page (that gets 404 back), you can
- use it to check your authentication protected web pages (that get a 401
+ use it to check your authentication protected web pages (that gets a 401
back) and so on.
The specific HTTP response code does not constitute a problem or error for
libcurl speak).
You can also use the -w option and the variable %{response_code} to extract
- the exact response code that was return in the response.
+ the exact response code that was returned in the response.
4.21 Why is there a HTTP/1.1 in my HTTP/2 request?
The reason for this is that we first generate the request to send using the
old 1.1 style and show that request in the verbose output, and then we
convert it over to the binary header-compressed HTTP/2 style. The actual
- "1.1" part from that request is then not actually used in the transfer. The
- binary HTTP/2 headers are not human readable.
+ "1.1" part from that request is then not actually used in the transfer.
+ The binary HTTP/2 headers are not human readable.
5. libcurl Issues
libcurl will reuse connections for all transfers that are made using the
same libcurl handle.
- When you use the easy interface, the connection cache is kept within the
- easy handle. If you instead use the multi interface, the connection cache
- will be kept within the multi handle and will be shared among all the easy
- handles that are used within the same multi handle.
+ When you use the easy interface the connection cache is kept within the easy
+ handle. If you instead use the multi interface, the connection cache will be
+ kept within the multi handle and will be shared among all the easy handles
+ that are used within the same multi handle.
5.7 Link errors when building libcurl on Windows!
you want to change name resolver function you must rebuild libcurl and tell
it to use a different function.
- - The non-IPv6 resolver that can use one out of four host name resolve calls
- (depending on what your system supports):
+ - The non-IPv6 resolver that can use one of four different host name resolve
+ calls (depending on what your system supports):
A - gethostbyname()
B - gethostbyname_r() with 3 arguments
5.12 Can I make libcurl fake or hide my real IP address?
No. libcurl operates on a higher level. Besides, faking IP address would
- imply sending IP packet with a made-up source address, and then you normally
+ imply sending IP packets with a made-up source address, and then you normally
get a problem with receiving the packet sent back as they would then not be
routed to you!
libcurl is a C library, it doesn't know anything about C++ member functions.
- You can overcome this "limitation" with a relative ease using a static
+ You can overcome this "limitation" with relative ease using a static
member function that is passed a pointer to the class:
// f is the pointer to your object.
- static YourClass::func(void *buffer, size_t sz, size_t n, void *f)
+ static size_t YourClass::func(void *buffer, size_t sz, size_t n, void *f)
{
// Call non-static member function.
static_cast<YourClass*>(f)->nonStaticFunction();
}
// This is how you pass pointer to the static function:
- curl_easy_setopt(hcurl, CURLOPT_WRITEFUNCTION, YourClass:func);
+ curl_easy_setopt(hcurl, CURLOPT_WRITEFUNCTION, YourClass::func);
curl_easy_setopt(hcurl, CURLOPT_WRITEDATA, this);
5.15 How do I get an FTP directory listing?
projects / platform / upstream / curl.git / blobdiff