Merge branch 'pan/unicode_printable_ranges'

* pan/unicode_printable_ranges:
  Adapt stdlib tests to ~tp detecting latin1 binaries
  Update primary bootstrap
  Make wx debugger use +pc flag when applicable
  Correct misspelled comments and space at lin ends
  Make ~tp output latin1 binaries as strings if possible
  Leave the +pc handling to io and io_lib_pretty
  Remove newly introduced warning in erlexec.c
  Make shell_SUITE:otp_10302 use +pc unicode when needed
  Fix io_proto_SUITE to handle the new io_lib_pretty:print
  Add testcase for +pc and io:printable_range/0
  Make printing of UTF-8 in binaries behave like lists.
  Document +pc flag and io:printable_range/0
  Add usage of and spec for io:printable_range/0
  Add +pc {latin1|unicode} switch and io:printable_range/0
  Fix some Unicode issues

OTP-18084

2 files changed, 25 insertions, 1 deletions

diff --git a/lib/stdlib/doc/src/io.xml b/lib/stdlib/doc/src/io.xml
index 63f814ad2e..90f24c4cbc 100644
--- a/lib/stdlib/doc/src/io.xml
+++ b/lib/stdlib/doc/src/io.xml
@@ -211,6 +211,18 @@
       </desc>
     </func>
     <func>
+      <name name="printable_range" arity="0"/>
+      <fsummary>Get user requested printable character range</fsummary>
+      <desc>
+	<p>Return the user requested range of printable Unicode characters.</p>
+	<p>The user can request a range of characters that are to be considered printable in heuristic detection of strings by the shell and by the formatting functions. This is done by supplying <c>+pc &lt;range&gt;</c> when starting Erlang.</p>
+	<p>Currently the only valid values for <c>&lt;range&gt;</c> are <c>latin1</c> and <c>unicode</c>. <c>latin1</c> means that only code points below 256 (with the exception of control characters etc) will be considered printable. <c>unicode</c> means that all printable characters in all unicode character ranges are considered printable by the io functions.</p>
+	<p>By default, Erlang is started so that only the <c>latin1</c> range of characters will indicate that a list of integers is a string.</p>
+	<p>The simplest way to utilize the setting is to call <seealso marker="io_lib#printable_list/1">io_lib:printable_list/1</seealso>, which will use the return value of this function to decide if a list is a string of printable characters or not.</p>
+	<note><p>In the future, this function may return more values and ranges. It is recommended to use the io_lib:printable_list/1 function to avoid compatibility problems.</p></note>
+      </desc>
+    </func>
+    <func>
       <name name="setopts" arity="1"/>
       <name name="setopts" arity="2"/>
       <fsummary>Set options</fsummary>
diff --git a/lib/stdlib/doc/src/io_lib.xml b/lib/stdlib/doc/src/io_lib.xml
index 001d34a7c2..3dac259477 100644
--- a/lib/stdlib/doc/src/io_lib.xml
+++ b/lib/stdlib/doc/src/io_lib.xml
@@ -301,7 +301,11 @@
       <fsummary>Test for a list of printable characters</fsummary>
       <desc>
         <p>Returns <c>true</c> if <c><anno>Term</anno></c> is a flat list of
-          printable Unicode characters, otherwise it returns <c>false</c>.</p>
+          printable characters, otherwise it returns <c>false</c>.</p>
+	  <p>What is a printable character in this case is determined by the
+	  <c>+pc</c> start up flag to the Erlang VM. See 
+	  <seealso marker="io#printable_range/0">io:printable_range/0</seealso> 
+	  and <seealso marker="erts:erl#erl">erl(1)</seealso>.</p>
       </desc>
     </func>
     <func>
@@ -312,6 +316,14 @@
           printable ISO-latin-1 characters, otherwise it returns <c>false</c>.</p>
       </desc>
     </func>
+    <func>
+      <name name="printable_unicode_list" arity="1"/>
+      <fsummary>Test for a list of printable Unicode characters</fsummary>
+      <desc>
+        <p>Returns <c>true</c> if <c><anno>Term</anno></c> is a flat list of
+          printable Unicode characters, otherwise it returns <c>false</c>.</p>
+      </desc>
+    </func>
   </funcs>
 </erlref>