--- /dev/null
+.\" **************************************************************************
+.\" * _ _ ____ _
+.\" * Project ___| | | | _ \| |
+.\" * / __| | | | |_) | |
+.\" * | (__| |_| | _ <| |___
+.\" * \___|\___/|_| \_\_____|
+.\" *
+.\" * Copyright (C) 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 https://curl.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.
+.\" *
+.\" * SPDX-License-Identifier: curl
+.\" *
+.\" **************************************************************************
+.TH libcurl-env-dbg 3 "18 September 2023" "libcurl" "libcurl"
+.SH NAME
+libcurl-env-dbg \- environment variables libcurl DEBUGBUILD understands
+.SH DESCRIPTION
+This is a set of variables only recognized and used if libcurl was built
+"debug enabled", which should never be true for a library used in production.
+These variables are intended for internal use only, subject to change and have
+many effects on the behavior of libcurl. Refer to the source code to determine
+how exactly they are being used.
+.RS
+.IP "CURL_ALTSVC_HTTP"
+Bypass the AltSvc HTTPS protocol restriction if this variable exists.
+.IP "CURL_DBG_SOCK_RBLOCK"
+The percentage of recv() calls that should be answered with a EAGAIN at random.
+For TCP/UNIX sockets.
+.IP "CURL_DBG_SOCK_RMAX"
+The maximum data that shall be received from the network in one recv() call.
+For TCP/UNIX sockets. This is applied to every recv.
+
+Example: \fBCURL_DBG_SOCK_RMAX=400\fP means recv buffer size is limited to a
+maximum of 400 bytes.
+.IP "CURL_DBG_SOCK_WBLOCK"
+The percentage of send() calls that should be answered with a EAGAIN at random.
+For TCP/UNIX sockets.
+.IP "CURL_DBG_SOCK_WPARTIAL"
+The percentage of data that shall be written to the network. For TCP/UNIX
+sockets. This is applied to every send.
+
+Example: \fBCURL_DBG_SOCK_WPARTIAL=80\fP means a send with 1000 bytes would
+only send 800.
+.IP "CURL_DBG_QUIC_WBLOCK"
+The percentage of send() calls that should be answered with EAGAIN at random.
+QUIC only.
+.IP "CURL_DEBUG"
+Trace logging behavior as an alternative to calling \fIcurl_global_trace(3)\fP.
+
+Example: \fBCURL_DEBUG=http/2\fP means trace details about HTTP/2 handling.
+.IP "CURL_DEBUG_SIZE"
+Fake the size returned by CURLINFO_HEADER_SIZE and CURLINFO_REQUEST_SIZE.
+.IP "CURL_GETHOSTNAME"
+Fake the local machine's unqualified hostname for NTLM and SMTP.
+.IP "CURL_HSTS_HTTP"
+Bypass the HSTS HTTPS protocol restriction if this variable exists.
+.IP "CURL_FORCETIME"
+A time of 0 is used for AWS signatures and NTLM if this variable exists.
+.IP "CURL_ENTROPY"
+A fixed faked value to use instead of a proper random number so that functions
+in libcurl that are otherwise getting random outputs can be tested for what
+they generate.
+.IP "CURL_SMALLREQSEND"
+An alternative size of HTTP data to be sent at a time only if smaller than the
+current.
+.IP "CURL_SMALLSENDS"
+An alternative size of socket data to be sent at a time only if smaller than
+the current.
+.IP "CURL_TIME"
+Fake unix timestamp to use for AltSvc, HSTS and CURLINFO variables that are
+time related.
+
+This variable can also be used to fake the data returned by some CURLINFO
+variables that are not time-related (such as CURLINFO_LOCAL_PORT), and in that
+case the value is not a timestamp.
+.IP "CURL_TRACE"
+LDAP tracing is enabled if this variable exists and its value is 1 or greater.
+
+OpenLDAP tracing is separate. Refer to CURL_OPENLDAP_TRACE.
+.IP "CURL_NTLM_WB_FILE"
+Debug-version of the \fIntlm-wb\fP executable.
+.IP "CURL_OPENLDAP_TRACE"
+OpenLDAP tracing is enabled if this variable exists and its value is 1 or
+greater. There's a number of debug levels, refer to \fIopenldap.c\fP comments.
+.RE
+.SH "SEE ALSO"
+.BR libcurl-env (3)
controls and changes behaviors. This is the full list of variables to set and
description of what they do. Also note that curl, the command line tool,
supports a set of additional environment variables independently of this.
+.RS
.IP "[scheme]_proxy"
When libcurl is given a URL to use in a transfer, it first extracts the scheme
part from the URL and checks if there is a given proxy set for that in its
.IP USER
User name to use when invoking the \fIntlm-wb\fP tool, if \fINTLMUSER\fP and
\fILOGNAME\fP were not set.
+.RE
.SH "Debug Variables"
-There is a set of variables only recognized and used if libcurl was built
-"debug enabled", which should never be true for a library used in production.
-.IP "CURL_GETHOSTNAME"
-Debug-only variable.
-.IP "CURL_FORCETIME"
-Debug-only variable.
-.IP "CURL_ENTROPY"
-Debug-only variable. Used to set a fixed faked value to use instead of a
-proper random number so that functions in libcurl that are otherwise getting
-random outputs can be tested for what they generate.
-.IP "CURL_TRACE"
-Debug-only variable. Used for debugging the lib/ldap implementation.
-.IP "CURL_NTLM_WB_FILE"
-Debug-only variable. Used to set to a debug-version of the \fIntlm-wb\fP
-executable.
-.IP "CURL_OPENLDAP_TRACE"
-Debug-only variable. Used for debugging the OpenLDAP implementation.
+Debug variables are intended for internal use and are documented in
+\fIlibcurl-env-dbg(3)\fP.
+.SH "SEE ALSO"
+.BR libcurl-env-dbg (3)
projects / thirdparty / curl.git / commitdiff
