Re^2: binmode i/o for perl -pi in-place editing

oops, yes. Thanks. Either I didn't hit Next> enough times when I Super Searched before, or I had a typo, because I didn't find that or a few other similar ones (especially in place edit - how to do).

Tomorrow, I'll have to try the ARGVOUT filehandle from the latter, and the -Mopen=IN,:bytes,OUT,:bytes derived from the former, and see whether one or both help. The other thought I had, while driving home, was that maybe I could grab the select-returned filehandle, and see whether that's the current loop's output handle (I would think so; I'll test it out tomorrow)

And I'm really disappointed I didn't notice the ARGVOUT when reading perlrun, because it was literally just a few lines down from where I was reading in the perldocs, and I should have seen it. :-( Oh, well. Hopefully, good news tomorrow.

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Re^3: binmode i/o for perl -pi in-place editing by pryrt (Abbot) on Dec 08, 2016 at 16:20 UTC
So, what I learned: `\ARGV` and `${^LAST_FH}` do refer to the same file `\ARGVOUT` and `my $sh = select;` do refer to the same file Almost sufficient: `perl -pi.orig -e "binmode ARGV; binmode ARGVOUT; s/w/v/g" src.bin` : seemed to confirm that source file and output file were same length. I couldn't get `perl -pi.orig -Mopen=IN,:bytes,OUT,:bytes -e "s/w/v/g" src.bin` to work the same as the dual bin-mode (I tried with :raw vs :bytes, and only the IN or OUT or both... Unfortunately, even with the binmode, I found it wasn't sufficient: changing the input file so the first null-separated record (aka "line") has all the various EOL-like sequences showed me wrong: `perl -e "binmode STDOUT; $,=qq(\0); print qq(n\nr\rnr\n\rrn\r\nend), qw(encoded file), qq(r:\r\0n:\n\0nr:\n\r\0rn:\r\n), qw(with EOL-like sequences)" > src.bin` ⇒ `perl -pi pi.pl src.bin & dir src.bin*` ⇒ the output is one byte shorter than the input, because the `binmode(ARGV)` is too late for the first read (as was mentioned in the binmode and one-liners). Also, I'd lost the `$/=qq(\0)` at some point in the BEGIN block; when I re-inserted that, I found it wasn't working (because the first record had only been reading to the first newline, instead of the first null, and thus masking the fact that binmode wasn't applied for the first read). I tried doing some tricks with `eof` (with or without empty parentheses), to no avail. I tried doing `BEGIN { ...; binmode ARGV; }`, but it didn't help At this point, I'm just going to give in do it without the magic `-pi`. It frustrates me that I cannot get this, but since I have a less magic way working, I guess I'll have to live with it.	[reply] [d/l] [select]
Re^4: binmode i/o for perl -pi in-place editing by shmem (Chancellor) on Dec 08, 2016 at 22:48 UTC
I still don't do Windows, but I do have a virtual machine with strawberry perl v5.20.2 installed. Unfortunately, even with the binmode, I found it wasn't sufficient: changing the input file so the first null-separated record (aka "line") has all the various EOL-like sequences showed me wrong: `perl -e "binmode STDOUT; $,=qq(\0); print qq(n\nr\rnr\n\rrn\r\nend), qw(encoded file), qq(r:\r\0n:\n\0nr:\n\r\0rn:\r\n), qw(with EOL-like sequences)" > src.bin` ⇒ `perl -pi pi.pl src.bin & dir src.bin` ⇒ the output is one byte shorter than the input, because the `binmode(ARGV)` is too late for the first read (as was mentioned in the binmode and one-liners). Also, I'd lost the `$/=qq(\0)` at some point in the BEGIN block; when I re-inserted that, I found it wasn't working (because the first record had only been reading to the first newline, instead of the first null, and thus masking the fact that binmode wasn't applied for the first read). In your `pi.bat` (which you named windows cmd.exe* in the OP) file I changed this line: `- perl -pi.orig pi.pl src.bin + perl -Mopen=IO,:raw -pi.orig pi.pl src.bin` [download] and lo! both the original and the modified file have the same size, and identical content but for `s/w/v/g`. With your `src.bin` as per the above quotation, running `perl -Mopen=IO,:raw -pi.bak -e "s/w/v/g" src.bin` again produced the same result. Either you are getting your test cases mixed up, or something weird is happening. What perl version do you run? perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'	[reply] [d/l] [select]
Re^5: binmode i/o for perl -pi in-place editing by pryrt (Abbot) on Dec 09, 2016 at 14:44 UTC
++shmem. Today, when I try either `perl -Mopen=IO,:raw -pi.orig pi.pl src.bin` or `perl -Mopen=IN,:raw,OUT,:raw -pi.orig pi.pl src.bin` ... it works (file length stays the same with the original). I could have sworn I'd tried the second version, but maybe I had mixed up my test cases, like you said. Good to know that it can actually be done using the `-pi` magic notation. Thanks again.	[reply] [d/l] [select]