un-nest curl

curl-8.15.0/docs/libcurl/libcurl-env-dbg.md

@@ -0,0 +1,171 @@
+---
+c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+SPDX-License-Identifier: curl
+Title: libcurl-env-dbg
+Section: 3
+Source: libcurl
+See-also:
+  - libcurl-env (3)
+Protocol:
+  - All
+Added-in: n/a
+---
+
+# NAME
+
+libcurl-env-dbg - environment variables libcurl DEBUGBUILD understands
+
+# 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.
+
+## `CURL_ALTSVC_HTTP`
+
+Bypass the AltSvc HTTPS protocol restriction if this variable exists.
+
+## `CURL_DBG_SOCK_RBLOCK`
+
+The percentage of recv() calls that should be answered with an EAGAIN at
+random. For TCP/UNIX sockets.
+
+## `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: **CURL_DBG_SOCK_RMAX=400** means recv buffer size is limited to a
+maximum of 400 bytes.
+
+## `CURL_DBG_SOCK_WBLOCK`
+
+The percentage of send() calls that should be answered with an EAGAIN at
+random. For TCP/UNIX sockets.
+
+## `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: **CURL_DBG_SOCK_WPARTIAL=80** means a send with 1000 bytes would
+only send 800.
+
+## `CURL_DBG_QUIC_WBLOCK`
+
+The percentage of send() calls that should be answered with EAGAIN at random.
+QUIC only.
+
+## `CURL_DEBUG`
+
+Trace logging behavior as an alternative to calling curl_global_trace(3).
+
+Example: **CURL_DEBUG=http/2** means trace details about HTTP/2 handling.
+
+In the curl command line tool, built with `--enable-debug`, this environment
+variable adds to arguments like `--verbose`, `-vvv`. At least a single `-v`
+is needed to make the run emit trace output, but when it does, the contents
+of `CURL_DEBUG` are added and can override existing options.
+
+Example: **CURL_DEBUG=tcp,-http/2 curl -vv url** means trace protocol details,
+triggered by `-vv`, add tracing of TCP in addition and remove tracing of
+HTTP/2.
+
+## `CURL_DEBUG_SIZE`
+
+Fake the size returned by CURLINFO_HEADER_SIZE and CURLINFO_REQUEST_SIZE.
+
+## `CURL_DNS_SERVER`
+
+When built with c-ares for name resolving, setting this environment variable
+to `[IP:port]` makes libcurl use that DNS server instead of the system
+default. This is used by the curl test suite.
+
+## `CURL_FTP_PWD_STOP`
+
+When set, the first transfer - when using ftp: - returns before sending
+the `PWD` command and stop any further progress. This is used to test
+an edge case
+
+## `CURL_GETHOSTNAME`
+
+Fake the local machine's unqualified hostname for NTLM and SMTP.
+
+## `CURL_HSTS_HTTP`
+
+Bypass the HSTS HTTPS protocol restriction if this variable exists.
+
+## `CURL_FORCETIME`
+
+A time of 0 is used for AWS signatures and NTLM if this variable exists.
+
+## `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.
+
+## `CURL_SMALLREQSEND`
+
+An alternative size of HTTP data to be sent at a time only if smaller than the
+current.
+
+## `CURL_SMALLSENDS`
+
+An alternative size of socket data to be sent at a time only if smaller than
+the current.
+
+## `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.
+
+## `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.
+
+## `CURL_OPENLDAP_TRACE`
+
+OpenLDAP tracing is enabled if this variable exists and its value is 1 or
+greater. There is a number of debug levels, refer to *openldap.c* comments.
+
+## `CURL_WS_CHUNK_SIZE`
+
+Used to influence the buffer chunk size used for WebSocket encoding and
+decoding.
+
+## `CURL_WS_CHUNK_EAGAIN`
+
+Used to simulate blocking sends after this chunk size for WebSocket
+connections.
+
+## `CURL_WS_FORCE_ZERO_MASK`
+
+Used to set the bitmask of all sent WebSocket frames to zero. The value of the
+environment variable does not matter.
+
+## `CURL_FORBID_REUSE`
+
+Used to set the CURLOPT_FORBID_REUSE flag on each transfer initiated
+by the curl command line tool. The value of the environment variable
+does not matter.
+
+## `CURL_GRACEFUL_SHUTDOWN`
+
+Make a blocking, graceful shutdown of all remaining connections when
+a multi handle is destroyed. This implicitly triggers for easy handles
+that are run via easy_perform. The value of the environment variable
+gives the shutdown timeout in milliseconds.
+
+## `CURL_H2_STREAM_WIN_MAX`
+
+Set to a positive 32-bit number to override the HTTP/2 stream window's
+default of 10MB. Used in testing to verify correct window update handling.