+.TP
+.I "MONO_GAC_PREFIX"
+Provides a prefix the runtime uses to look for Global Assembly Caches.
+Directories are separated by the platform path separator (colons on
+unix). MONO_GAC_PREFIX should point to the top directory of a prefixed
+install. Or to the directory provided in the gacutil /gacdir command. Example:
+.B /home/username/.mono:/usr/local/mono/
+.TP
+.I "MONO_LOG_LEVEL"
+The logging level, possible values are `error', `critical', `warning',
+`message', `info' and `debug'. See the DEBUGGING section for more
+details.
+.TP
+.I "MONO_LOG_MASK"
+Controls the domain of the Mono runtime that logging will apply to.
+If set, the log mask is changed to the set value. Possible values are
+"asm" (assembly loader), "type", "dll" (native library loader), "gc"
+(garbage collector), "cfg" (config file loader), "aot" (precompiler) and "all".
+The default value is "all". Changing the mask value allows you to display only
+messages for a certain component. You can use multiple masks by comma
+separating them. For example to see config file messages and assembly loader
+messages set you mask to "asm,cfg".
+.TP
+.I "MONO_MANAGED_WATCHER"
+If set to any value, System.IO.FileSystemWatcher will use the default
+managed implementation (slow). If unset, mono will try to use FAM under
+Unix systems and native API calls on Windows, falling back to the
+managed implementation on error.
+.TP
+.I "MONO_PATH"
+Provides a search path to the runtime where to look for library files.
+Directories are separated by the platform path separator (colons on unix). Example:
+.B /home/username/lib:/usr/local/mono/lib
+.TP
+.I "MONO_RTC"
+Experimental RTC support in the statistical profiler: if the user has
+the permission, more accurate statistics are gathered. The MONO_RTC
+value must be restricted to what the linux rtc allows: power of two
+from 64 to 8192 Hz. To enable higher frequencies like 4096 Hz, run as root:
+.nf
+ echo 4096 > /proc/sys/dev/rtc/max-user-freq
+.fi
+.Sp
+For example:
+.nf
+ MONO_RTC=4096 mono --profiler=default:stat program.exe
+.fi
+.TP
+.I "MONO_NO_TLS"
+Disable inlining of thread local accesses. Try setting this if you get a segfault
+early on in the execution of mono.