1--- 2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 3SPDX-License-Identifier: curl 4Title: libcurl-env-dbg 5Section: 3 6Source: libcurl 7See-also: 8 - libcurl-env (3) 9Protocol: 10 - All 11--- 12 13# NAME 14 15libcurl-env-dbg - environment variables libcurl DEBUGBUILD understands 16 17# DESCRIPTION 18 19This is a set of variables only recognized and used if libcurl was built 20"debug enabled", which should never be true for a library used in production. 21These variables are intended for internal use only, subject to change and have 22many effects on the behavior of libcurl. Refer to the source code to determine 23how exactly they are being used. 24 25## CURL_ALTSVC_HTTP 26 27Bypass the AltSvc HTTPS protocol restriction if this variable exists. 28 29## CURL_DBG_SOCK_RBLOCK 30 31The percentage of recv() calls that should be answered with a EAGAIN at random. 32For TCP/UNIX sockets. 33 34## CURL_DBG_SOCK_RMAX 35 36The maximum data that shall be received from the network in one recv() call. 37For TCP/UNIX sockets. This is applied to every recv. 38 39Example: **CURL_DBG_SOCK_RMAX=400** means recv buffer size is limited to a 40maximum of 400 bytes. 41 42## CURL_DBG_SOCK_WBLOCK 43 44The percentage of send() calls that should be answered with a EAGAIN at random. 45For TCP/UNIX sockets. 46 47## CURL_DBG_SOCK_WPARTIAL 48 49The percentage of data that shall be written to the network. For TCP/UNIX 50sockets. This is applied to every send. 51 52Example: **CURL_DBG_SOCK_WPARTIAL=80** means a send with 1000 bytes would 53only send 800. 54 55## CURL_DBG_QUIC_WBLOCK 56 57The percentage of send() calls that should be answered with EAGAIN at random. 58QUIC only. 59 60## CURL_DEBUG 61 62Trace logging behavior as an alternative to calling curl_global_trace(3). 63 64Example: **CURL_DEBUG=http/2** means trace details about HTTP/2 handling. 65 66## CURL_DEBUG_SIZE 67 68Fake the size returned by CURLINFO_HEADER_SIZE and CURLINFO_REQUEST_SIZE. 69 70## CURL_GETHOSTNAME 71 72Fake the local machine's unqualified hostname for NTLM and SMTP. 73 74## CURL_HSTS_HTTP 75 76Bypass the HSTS HTTPS protocol restriction if this variable exists. 77 78## CURL_FORCETIME 79 80A time of 0 is used for AWS signatures and NTLM if this variable exists. 81 82## CURL_ENTROPY 83 84A fixed faked value to use instead of a proper random number so that functions 85in libcurl that are otherwise getting random outputs can be tested for what 86they generate. 87 88## CURL_SMALLREQSEND 89 90An alternative size of HTTP data to be sent at a time only if smaller than the 91current. 92 93## CURL_SMALLSENDS 94 95An alternative size of socket data to be sent at a time only if smaller than 96the current. 97 98## CURL_TIME 99 100Fake unix timestamp to use for AltSvc, HSTS and CURLINFO variables that are 101time related. 102 103This variable can also be used to fake the data returned by some CURLINFO 104variables that are not time-related (such as CURLINFO_LOCAL_PORT), and in that 105case the value is not a timestamp. 106 107## CURL_TRACE 108 109LDAP tracing is enabled if this variable exists and its value is 1 or greater. 110 111OpenLDAP tracing is separate. Refer to CURL_OPENLDAP_TRACE. 112 113## CURL_NTLM_WB_FILE 114 115Debug-version of the *ntlm-wb* executable. 116 117## CURL_OPENLDAP_TRACE 118 119OpenLDAP tracing is enabled if this variable exists and its value is 1 or 120greater. There is a number of debug levels, refer to *openldap.c* comments. 121 122## CURL_WS_CHUNK_SIZE 123 124Used to influence the buffer chunk size used for WebSocket encoding and 125decoding. 126
