diff options
Diffstat (limited to 'erts/doc/src/erlang.xml')
| -rw-r--r-- | erts/doc/src/erlang.xml | 30 |
1 files changed, 23 insertions, 7 deletions
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml index bd5efb712c..ba5f80a9c1 100644 --- a/erts/doc/src/erlang.xml +++ b/erts/doc/src/erlang.xml @@ -1339,10 +1339,11 @@ true <fsummary>Check if a function is exported and loaded</fsummary> <desc> <p>Returns <c>true</c> if the module <c><anno>Module</anno></c> is loaded - and contains an exported function <c><anno>Function</anno>/<anno>Arity</anno></c>; - otherwise <c>false</c>.</p> - <p>Returns <c>false</c> for any BIF (functions implemented in C - rather than in Erlang).</p> + and contains an exported function <c><anno>Function</anno>/<anno>Arity</anno></c>, + or if there is a BIF (a built-in function implemented in C) + with the given name; otherwise returns <c>false</c>.</p> + <note><p>This function used to return false for built-in + functions before the 18.0 release.</p></note> </desc> </func> <func> @@ -1443,7 +1444,7 @@ true <name name="get" arity="1"/> <fsummary>Return a value from the process dictionary</fsummary> <desc> - <p>Returns the value <c><anno>Val</anno></c>associated with <c><anno>Key</anno></c> in + <p>Returns the value <c><anno>Val</anno></c> associated with <c><anno>Key</anno></c> in the process dictionary, or <c>undefined</c> if <c><anno>Key</anno></c> does not exist.</p> <pre> @@ -1463,6 +1464,19 @@ true </desc> </func> <func> + <name name="get_keys" arity="0"/> + <fsummary>Return a list of all keys from the process dictionary</fsummary> + <desc> + <p>Returns a list of keys all keys present in the process dictionary.</p> + <pre> +> <input>put(dog, {animal,1}),</input> +<input>put(cow, {animal,2}),</input> +<input>put(lamb, {animal,3}),</input> +<input>get_keys().</input> +[dog,cow,lamb]</pre> + </desc> + </func> + <func> <name name="get_keys" arity="1"/> <fsummary>Return a list of keys from the process dictionary</fsummary> <desc> @@ -3057,7 +3071,7 @@ os_prompt% </pre> raised. The error reason may differ between operating systems. Typically the error <c>enoent</c> is raised when one tries to run a program that is not found and - <c>eaccess</c> is raised when the given file is not + <c>eacces</c> is raised when the given file is not executable.</p> </item> <tag><c>{fd, <anno>In</anno>, <anno>Out</anno>}</c></tag> @@ -7365,7 +7379,9 @@ timestamp() -> only allowed with <c>PidSpec==all</c>. If the host machine operating system does not support high resolution CPU time measurements, <c>trace/3</c> exits with - <c>badarg</c>.</p> + <c>badarg</c>. Note that most operating systems do + not synchronize this value across cores, so be prepared + that time might seem to go backwards when using this option.</p> </item> <tag><c>arity</c></tag> <item> |