Retract #20826 and #20831; things are done differently

[p5sagit/p5-mst-13.2.git] / pod / perlrun.pod

diff --git a/pod/perlrun.pod b/pod/perlrun.pod
index 730c75d..3ddb2f8 100644 (file)
--- a/pod/perlrun.pod
+++ b/pod/perlrun.pod
@@ -127,7 +127,7 @@ as the first line in C<*.cmd> file (B<-S> due to a bug in cmd.exe's
 =item MS-DOS
 
 Create a batch file to run your program, and codify it in
-C<ALTERNATIVE_SHEBANG> (see the F<dosish.h> file in the source
+C<ALTERNATE_SHEBANG> (see the F<dosish.h> file in the source
 distribution for more information).
 
 =item Win95/NT
@@ -894,11 +894,13 @@ used.
 
 =item PERL5LIB
 
-A colon-separated list of directories in which to look for Perl library
+A list of directories in which to look for Perl library
 files before looking in the standard library and the current
 directory.  Any architecture-specific directories under the specified
 locations are automatically included if they exist.  If PERL5LIB is not
-defined, PERLLIB is used.
+defined, PERLLIB is used.  Directories are separated (like in PATH) by
+a colon on unixish platforms and by a semicolon on Windows (the proper
+path separator being given by the command C<perl -V:path_sep>).
 
 When running taint checks (either because the program was running setuid
 or setgid, or the B<-T> switch was used), neither variable is used.
@@ -945,9 +947,23 @@ You perhaps were thinking of C<:crlf:bytes> or C<:perlio:bytes>.
 
 =item :crlf
 
-A layer that implements DOS/Windows like CRLF line endings.
-On read converts pairs of CR,LF to a single "\n" newline character.
-On write converts each "\n" to a CR,LF pair.
+A layer that implements DOS/Windows like CRLF line endings.  On read
+converts pairs of CR,LF to a single "\n" newline character.  On write
+converts each "\n" to a CR,LF pair.  Note that this layer likes to be
+one of its kind: it silently ignores attempts to be pushed into the
+layer stack more than once.
+
+(Gory details follow) To be more exact what happens is this: after
+pushing itself to the stack, the C<:crlf> layer checks all the layers
+below itself to find the first layer that is capable of being a CRLF
+layer but is not yet enabled to be a CRLF layer.  If it finds such a
+layer, it enables the CRLFness of that other deeper layer, and then
+pops itself off the stack.  If not, fine, use the one we just pushed.
+
+The end result is that a C<:crlf> means "please enable the first CRLF
+layer you can find, and if you can't find one, here would be a good
+spot to place a new one."
+
 Based on the C<:perlio> layer.
 
 =item :mmap
@@ -1062,7 +1078,7 @@ and Win32 approximate equivalent:
 
 =item PERLLIB
 
-A colon-separated list of directories in which to look for Perl library
+A list of directories in which to look for Perl library
 files before looking in the standard library and the current directory.
 If PERL5LIB is defined, PERLLIB is not used.