box86/docs/USAGE.md

Usage
----

There are many environment variables to control Box86 behaviour. 

#### BOX86_LOG
Controls the Verbosity level of the logs
 * 0: NONE : No message (except some fatal error). (Default.)
 * 1: INFO : Show some minimum log (Example: librairies not found)
 * 2: DEBUG : Details a lot of stuff (Example: relocations or functions called).
 * 3: DUMP : All DEBUG plus DUMP of all ELF Info.

#### BOX86_NOBANNER
Disables Box86 printing its version and build
 * 0 : Enable printing its banner. (Default.)
 * 1 : Disable printing its banner. 

#### BOX86_LD_LIBRARY_PATH
Path to look for x86 libraries. Default is current folder and `lib` in current folder.
Also, `/usr/lib/i386-linux-gnu` and `/lib/i386-linux-gnu` are added if they exist.

#### BOX86_PATH
Path to look for x86 executable. Default is current folder and `bin` in current folder.

#### BOX86_DLSYM_ERROR
Enables/Disables the logging of `dlsym` errors.
 * 0 : Don't log `dlsym` errors. (Default.)
 * 1 : Log dlsym errors.

#### BOX86_TRACE_FILE
Send all log and trace to a file instead of `stdout`
Also, if name contains `%pid` then this is replaced by the actual PID of box86 instance

#### BOX86_TRACE
Only on build with trace enabled. Trace allow the logging of all instruction executed, along with register dump
 * 0 : No trace. (Default.) 
 * 1 : Trace enabled. Trace start after the initialisation of all depending libraries is done.
 * symbolname : Trace only `symbolname` (trace is disable if the symbol is not found).
 * 0xXXXXXXX-0xYYYYYYY : Trace only between the 2 addresses.

#### BOX86_TRACE_INIT
Use BOX86_TRACE_INIT instead of BOX_TRACE to start trace before the initialisation of libraries and the running program
 * 0 : No trace. (Default.)
 * 1 : Trace enabled. The trace start with the initialisation of all depending libraries is done.

#### BOX86_TRACE_START
Only on builds with trace enabled.
 * NNNNNNN : Start trace only after NNNNNNNN opcode execute (number is an `uint64_t`).

#### BOX86_TRACE_XMM
Only on builds with trace enabled.
 * 0 : The XMM (i.e. SSE/SSE2) register will not be logged with the general and x86 registers. (Default.)
 * 1 : Dump the XMM registers.

#### BOX86_LOAD_ADDR
Try to load at 0xXXXXXX main binary (if binary is a PIE)
 * 0xXXXXXXXX : The load address . (Only active on PIE programs.)

#### BOX86_NOSIGSEGV
Disable handling of SigSEGV. (Very useful for debugging.)
 * 0 : Let the x86 program set sighandler for SEGV (Default.)
 * 1 : Disable the handling of SigSEGV.

#### BOX86_NOSIGILL
Disable handling of SigILL (to ease debugging mainly).
 * 0 : Let x86 program set sighandler for Illegal Instruction
 * 1 : Disables the handling of SigILL 

#### BOX86_X11COLOR16
PANDORA only: Try converting X11 color from 32 bits to 16 bits (to avoid light green on light cyan windows).
 * 0 : Don't touch X11 colors. (Default.)
 * 1 : Change colors arguments in XSetForeground, XSetBackground and XCreateGC.

#### BOX86_X11THREADS
Call XInitThreads when loading X11. (This is mostly for old Loki games with the Loki_Compat library.)
 * 0 : Don't force call XInitThreads. (Default.)
 * 1 : Call XInitThreads as soon as libX11 is loaded.

#### BOX86_X11GLX
Force libX11's GLX extension to be present.
* 0 : Do not force libX11's GLX extension to be present. 
* 1 : GLX will always be present when using XQueryExtension. (Default.)

#### BOX86_DYNAREC_DUMP
Enables/disables Box86's Dynarec's dump.
 * 0 : Disable Dynarec's blocks dump. (Default.)
 * 1 : Enable Dynarec's blocks dump.
 * 2 : Enable Dynarec's blocks dump with some colors.

#### BOX86_DYNAREC_LOG
Set the level of DynaRec's logs.
 * 0 : NONE : No Logs for DynaRec. (Default.)
 * 1 :INFO : Minimum Dynarec Logs (only unimplemented OpCode).
 * 2 : DEBUG : Debug Logs for Dynarec (with details on block created / executed).
 * 3 : VERBOSE : All of the above plus more.

#### BOX86_DYNAREC
Enables/Disables Box86's Dynarec.
 * 0 : Disables Dynarec.
 * 1 : Enable Dynarec. (Default.)

#### BOX86_DYNAREC_TRACE
Enables/Disables trace for generated code.
 * 0 : Disable trace for generated code. (Default.)
 * 1 : Enable trace for generated code (like regular Trace, this will slow down the program a lot and generate huge logs).

#### BOX86_NODYNAREC 
Forbid dynablock creation in the interval specified (helpfull for debugging behaviour difference between Dynarec and Interpretor)
 * 0xXXXXXXXX-0xYYYYYYYY : define the interval where dynablock cannot start (inclusive-exclusive)

#### BOX86_LIBGL
 * libXXXX set the name for libGL (defaults to libGL.so.1).
 * /PATH/TO/libGLXXX : Sets the name and path for libGL
 You can also use SDL_VIDEO_GL_DRIVER

#### BOX86_LD_PRELOAD
 * XXXX[:YYYYY] force loading XXXX (and YYYY...) libraries with the binary
 PreLoaded libs can be emulated or native, and are treated the same way as if they were comming from the binary
 
#### BOX86_EMULATED_LIBS
 * XXXX[:YYYYY] force lib XXXX (and YYYY...) to be emulated (and not wrapped)
Some games uses an old version of some libraries, with an ABI incompatible with native version.
Note that LittleInferno for example is auto detected, and libvorbis.so.0 is automatical added to emulated libs, and same for Don't Starve (and Together / Server variant) that use an old SDL2 too

#### BOX86_ALLOWMISSINGLIBS
Allow Box86 to continue even if a library is missing.
 * 0 : Box86 will stop if a library cannot be loaded. (Default.)
 * 1 : Continue even if a needed library cannot be loaded. Unadvised, this will, in most cases, crash later on.

#### BOX86_NOPULSE
Disables the load of pulseaudio libraries.
 * 0 : Load pulseaudio libraries if found. (Default.)
 * 1 : Disables the load of pulse audio libraries (libpulse and libpulse-simple), both the native library and the x86 library

#### BOX86_NOGTK
Disables the loading of wrapped GTK libraries.
 * 0 : Load wrapped GTK libraries if found. (Default.)
 * 1 : Disables loading wrapped GTK libraries (can be used with Steam, along with STEAM_RUNTIME=1 to use the i386 version of GTK).

#### BOX86_NOVULKAN
Disables the load of vulkan libraries.
 * 0 : Load vulkan libraries if found.
 * 1 : Disables the load of vulkan libraries, both the native and the i386 version (can be useful on Pi4, where the vulkan driver is not quite there yet.)

#### BOX86_FIX_64BIT_INODES
Fix/Don't fix 64bit inodes
 * 0 : Don't fix 64bit inodes. (Default.)
 * 1 : Fix 64bit inodes. Helps when running on Filesystems with 64bit inodes. Is useful when a program uses API functions which doesn't support it and the program doesn't use inodes information.

#### BOX86_JITGDB

 * 0 : Just print the Segfault message on segfault (default)
 * 1 : Launch `gdb` when a segfault, bus error or illegal instruction signal is trapped, attached to the offending process and go in an endless loop, waiting.
 When in gdb, you need to find the correct thread yourself (the one with `my_box86signalhandler` in is stack)
 then probably need to `finish` 1 or 2 functions (inside `usleep(..)`) and then you'll be in `my_box86signalhandler`, 
 just before the printf of the Segfault message. Then simply 
 `set waiting=0` to exit the infinite loop.
 * 2 : Launch `gdbserver` when a segfault, bus error or illegal instruction signal is trapped, attached to the offending process, and go in an endless loop, waiting.
 Use `gdb /PATH/TO/box86` and then `target remote 127.0.0.1:1234` to connect to the gdbserver (or use actual IP if not on the machine). After that, the procedure is the same as with ` BOX86_JITGDB=1`.
 This mode can be usefullwhen programs redirect all console output to a file (like Unity3D Games)