Introduce LTTNG_UST_APP_PATH environment variable

[lttng-ust.git] / doc / man / lttng-ust.3.txt

diff --git a/doc/man/lttng-ust.3.txt b/doc/man/lttng-ust.3.txt
index 55b2b20dedba75e6895d9fe4147f7e579b34d90f..081388961f4994553a4b80083c4e0427ed5a1af4 100644 (file)
--- a/doc/man/lttng-ust.3.txt
+++ b/doc/man/lttng-ust.3.txt
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2016 Philippe Proulx <pproulx@efficios.com>
+// SPDX-License-Identifier: CC-BY-4.0
+//
 lttng-ust(3)
 ============
 :object-type: library
@@ -81,7 +84,11 @@ SYNOPSIS
 #define *lttng_ust_tracepoint*('prov_name', 't_name', ...)
 #define *lttng_ust_tracepoint_enabled*('prov_name', 't_name')
 
-Link with `-llttng-ust -llttng-ust-common -ldl`, following this man page.
+Link with, following this manual page:
+
+* `-llttng-ust -ldl`
+* If you define `_LGPL_SOURCE` before including
+  `<lttng/tracepoint.h>` (directly or indirectly): `-llttng-ust-common`
 
 
 DESCRIPTION
@@ -728,12 +735,12 @@ change, but need not to be otherwise recompiled (unless the tracepoint
 provider's API changes).
 
 Then, link your application with this object file (or with the static
-library containing it) and with `liblttng-ust`, `liblttng-ust-common`,
-and `libdl` (`libc` on a BSD system):
+library containing it) and with `liblttng-ust` and `libdl` (`libc` on a
+BSD system):
 
 [role="term"]
 ----
-$ cc -o app tp.o app.o -llttng-ust -llttng-ust-common -ldl
+$ cc -o app tp.o app.o -llttng-ust -ldl
 ----
 
 
@@ -783,8 +790,7 @@ It is then linked as a shared library like this:
 
 [role="term"]
 ----
-$ cc -shared -Wl,--no-as-needed -o tp.so tp.o -llttng-ust \
-     -llttng-ust-common
+$ cc -shared -Wl,--no-as-needed -o tp.so tp.o -llttng-ust
 ----
 
 This tracepoint provider shared object isn't linked with the user
@@ -1218,7 +1224,7 @@ like this:
 ----
 $ cc -c -I. tp.c
 $ cc -c app.c
-$ cc -o app tp.o app.o -llttng-ust -llttng-ust-common -ldl
+$ cc -o app tp.o app.o -llttng-ust -ldl
 ----
 
 Using the man:lttng(1) tool, create an LTTng tracing session, enable
@@ -1476,15 +1482,22 @@ int main(int argc, char* argv[])
 
 ENVIRONMENT VARIABLES
 ---------------------
+`LTTNG_UST_APP_PATH`::
+    Path under which unix sockets used for the communication between
+    the application (tracee) instrumented with `liblttng-ust` and the
+    LTTng session and consumer daemons (part of the LTTng-tools project)
+    are located. When `$LTTNG_UST_APP_PATH` is specified, only this path
+    is considered for connecting to a session daemon. The
+    `$LTTNG_UST_APP_PATH` target directory must exist and be accessible
+    by the user before the application is executed for tracing to work.
+    Setting this environment variable disables connection to root and
+    per-user session daemons.
+
 `LTTNG_HOME`::
     Alternative user's home directory. This variable is useful when the
     user running the instrumented application has a non-writable home
-    directory.
-+
-Unix sockets used for the communication between `liblttng-ust` and the
-LTTng session and consumer daemons (part of the LTTng-tools project)
-are located in a specific directory under `$LTTNG_HOME` (or `$HOME` if
-`$LTTNG_HOME` is not set).
+    directory. This path is where unix sockets for communication with
+    the per-user session daemon are located.
 
 `LTTNG_UST_ALLOW_BLOCKING`::
     If set, allow the application to retry event tracing when there's
@@ -1504,6 +1517,9 @@ prevent discarding event records.
 WARNING: Setting this environment variable may significantly
 affect application timings.
 
+`LTTNG_UST_ABORT_ON_CRITICAL`::
+    If set, abort the instrumented application on a critical error message.
+
 `LTTNG_UST_CLOCK_PLUGIN`::
     Path to the shared object which acts as the clock override plugin.
     An example of such a plugin can be found in the LTTng-UST