diff options
author | Father Chrysostomos <sprout@cpan.org> | 2011-02-19 18:01:42 -0800 |
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committer | Father Chrysostomos <sprout@cpan.org> | 2011-02-19 18:01:42 -0800 |
commit | 8eef6978dfd4059fb861f5604b6109cffa2cebee (patch) | |
tree | ecbd4cb6f10db2850a88ce8a704c73024c6ece47 /pod | |
parent | 42993a5c4912d5546ce7c95cae4169e1e613106c (diff) | |
download | perl-8eef6978dfd4059fb861f5604b6109cffa2cebee.tar.gz |
perlfilter tweaks
Diffstat (limited to 'pod')
-rw-r--r-- | pod/perlfilter.pod | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/pod/perlfilter.pod b/pod/perlfilter.pod index ca5cfd9fb2..27061883c1 100644 --- a/pod/perlfilter.pod +++ b/pod/perlfilter.pod @@ -217,7 +217,7 @@ difficult for the potential cracker. The most important: Write your decryption filter in C and statically link the decryption module into the Perl binary. For further tips to make life difficult for the potential cracker, see the file I<decrypt.pm> in the source filters -module. +distribution. =back @@ -234,7 +234,7 @@ The source filter distribution includes two modules that simplify this task: C<Filter::exec> and C<Filter::sh>. Both allow you to run any external executable. Both use a coprocess to control the flow of data into and out of the external executable. (For details on coprocesses, -see Stephens, W.R. "Advanced Programming in the UNIX Environment." +see Stephens, W.R., "Advanced Programming in the UNIX Environment." Addison-Wesley, ISBN 0-210-56317-7, pages 441-445.) The difference between them is that C<Filter::exec> spawns the external command directly, while C<Filter::sh> spawns a shell to execute the external @@ -388,9 +388,9 @@ Two special marker lines will bracket debugging code, like this: } ## DEBUG_END -When the C<DEBUG> environment variable exists, the filter ensures that -Perl parses only the code between the C<DEBUG_BEGIN> and C<DEBUG_END> -markers. That means that when C<DEBUG> does exist, the code above +The filter ensures that Perl parses the code between the <DEBUG_BEGIN> +and C<DEBUG_END> markers only when the C<DEBUG> environment variable +exists. That means that when C<DEBUG> does exist, the code above should be passed through the filter unchanged. The marker lines can also be passed through as-is, because the Perl parser will see them as comment lines. When C<DEBUG> isn't set, we need a way to disable the |