diff options
Diffstat (limited to 'lib/kernel/doc/src/os.xml')
| -rw-r--r-- | lib/kernel/doc/src/os.xml | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/lib/kernel/doc/src/os.xml b/lib/kernel/doc/src/os.xml index 2d2a690fea..165160a909 100644 --- a/lib/kernel/doc/src/os.xml +++ b/lib/kernel/doc/src/os.xml @@ -37,6 +37,7 @@ use these functions can be of help in enabling a program to run on most platforms.</p> </description> + <funcs> <func> <name name="cmd" arity="1"/> @@ -171,8 +172,8 @@ DirOut = os:cmd("dir"), % on Win32 platform</code> </func> <func> <name name="timestamp" arity="0"/> - <type_desc variable="Timestamp">Timestamp = {MegaSecs, Secs, MicroSecs}</type_desc> <fsummary>Current OS system time on the erlang:timestamp/0 format</fsummary> + <type_desc variable="Timestamp">Timestamp = {MegaSecs, Secs, MicroSecs}</type_desc> <desc> <p>Returns current <seealso marker="erts:time_correction#OS_System_Time">OS system time</seealso> @@ -205,11 +206,35 @@ format_utc_timestamp() -> 29 Apr 2009 9:55:30.051711 </pre> <p>OS system time can also be retreived by - <c><seealso marker="#system_time/0"><c>os:system_time/0</c></seealso></c>, + <seealso marker="#system_time/0"><c>os:system_time/0</c></seealso>, and <seealso marker="#system_time/1"><c>os:system_time/1</c></seealso>.</p> </desc> </func> <func> + <name name="perf_counter" arity="0"/> + <fsummary>Returns a performance counter</fsummary> + <desc> + <p>Returns the current performance counter value in <c>perf_counter</c> + <seealso marker="erts:erlang#type_time_unit">time unit</seealso>. + This is a highly optimized call that might not be traceable. + </p> + </desc> + </func> + <func> + <name name="perf_counter" arity="1"/> + <fsummary>Returns a performance counter</fsummary> + <desc><p>Returns a performance counter that can be used as a very fast and + high resolution timestamp. This counter is read directly from the hardware or operating + system with the same guarantees. This means that two consecutive calls + to the function are not guaranteed to be monotonic, though it most likely will be. + The performance counter till be converted to the resolution passed as an argument.</p> + <pre>1> <input>T1 = os:perf_counter(1000),receive after 10000 -> ok end,T2 = os:perf_counter(1000).</input> +176525861 +2> <input>T2 - T1.</input> +10004</pre> + </desc> + </func> + <func> <name name="type" arity="0"/> <fsummary>Return the OS family and, in some cases, OS name of the current operating system</fsummary> <desc> |