* Package name    : esu
  Version         : 1.01
  Upstream Author : Eun <eun@su.am>
* URL             : https://github.com/Eun/ecp
* License         : GPLv3
  Programming Lang: C
  Description     : It allows to copy files with different checksums on the fly.

Basicly a replacement for cp with additional checksum on the fly support.
It allows MD5, SHA1, SHA224, SHA265, SHA384, SHA512 algorithm to be used.

How is this different from rsync? Quoting rsync(1):

       Rsync is a fast and extraordinarily versatile file  copying
       tool.   It can  copy  locally,  to/from  another  host  over
       any remote shell, or to/from a remote rsync daemon.
       [...]
               -c, --checksum              skip based on checksum,
                                           not mod-time & size

Best wishes,
Ryan

The difference is that ecp generates the checksum on the fly, this means it
is faster then rsync,
rsync copy's first and compares the sum of the source and destination
afterwards (4 operations).
esu saves one operation by calculating the checksum during reading the file.

to make it clearer:

rsync:
1. read srcfile
2. write dstfile
3. checksum of src
4. checksum of dst

ecp:
1. read srcfile, checksum of src
2. write dstfile
3. checksum of dst



2013/8/20 Ryan Kavanagh <rak@debian.org>

[...]

The package name is also very unfortunate: there's a ubiquitous tool,
called `su`, which has nothing to do with copying files.  I suspect the
name of this tools will provoke unnecessary confusion with `su`.

So my take on the tool's name would be to name it `cscp` (for "checksum
cp").  At least the archive does not seem to contain a binary named
like this [1].

1. http://packages.debian.org/search?searchon=contents&keywords=cscp&mode=path&suite=stable&arch=i386

I would rephrase both fields a bit, as follows.

"Copies a file calculating its checksum on the fly and printing it after
copying is completed."

^^^ Basically.
replacement for GNU `cp` is a complex tool with wide range of
possibilities such as:
* Copying whole hierarchies.
* Conditional file replacement -- only when the source file is newer
  ("updating");
* Preserving ownership and permissions.
* Copying (or not copying) of special files (such as FIFOs).
* Creating backups of the replaced files.
* Hardlinking instead of copying (including processing whole
  hierarchies).

So I would rephrase the description into something like this:
"This tools allows to copy one or more files calculating their checksum
on the fly as it transfers their data.  The checksums are printed to
the standard output.
.
The following checksumming algorythms are supported: MD5, SHA1...".

Hope this helps.

P.S.
On the tool's web page, in the "Usage" section, consider changing the
"-d               create empty directorys"
line to read
"-d               create empty directories"
as there's a common rule in English.

On Tue, 20 Aug 2013 10:21:05 -0400 Ryan Kavanagh <rak@debian.org> wrote:

It means "do not copy a file if its checksum on the receiver is the
same as on the sender", that is, this option just modifies the way
`rsync` detects whether a particular file should be updated on the
receiver.  The proposed tool combines (unconditional) copying with
calculating a checksum over the copied content.  At least that's how I
read it.

...

It would be helpful if the upstream README.md and the package description
explain what the checksums are for. Is this a replacement for cp+sha1sum
(or sha256sum or whatever algorithm is used), or is the checksum used
for verifying that the resulting file is copied correctly and has not
become corrupted during the copy? If the latter, does the program do
anything else to ensure a safe copy, such as fsync to make sure the
target file is committed to disk, or flushing kernel buffer caches so
that checksumming the target file happens on data that is read from the
target disk, and not from cache memory? Also an explanation of why this
is useful and why (and when) the kernel's usual mechanisms aren't enough
would be a good idea.

"cp, but with checksums" isn't a useful description of a program. Unless
the program's output includes the checksums (perhaps for later
verification), the checksums don't seem interesting to me as a user. They
seem like an implementation detail rather than an essential feature of
the program.

Package name should be "ecp", sorry misspelled that.

I fixed the README and improved some things.

Thanks for your feedback!


2013/8/20 Lars Wirzenius <liw@liw.fi>

retitle 720327 RFP: ecp -- copies files with checksum on the fly"
noowner 720327
tag 720327 - pending
thanks

Hi,

A long time ago, you expressed interest in packaging ecp. Unfortunately,
it seems that it did not happen. In Debian, we try not to keep ITP bugs open
for a too long time, as it might cause other prospective maintainers to
refrain from packaging the software.

This is an automatic email to change the status of ecp from ITP
(Intent to Package) to RFP (Request for Package), because this bug hasn't seen
any activity during the last 12 months.

If you are still interested in packaging ecp, please send a mail to
<control@bugs.debian.org> with:

 retitle 720327 ITP: ecp -- copies files with checksum on the fly"
 owner 720327 !
 thanks

It is also a good idea to document your progress on this ITP from time to
time, by mailing <720327@bugs.debian.org>.  If you need guidance on how to
package this software, please reply to this email, and/or contact the
debian-mentors@lists.debian.org mailing list.

Thank you for your interest in Debian,