How do you tag one file onto the end of another?
in [Windows XP New Users]
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From: J. P. Gilliver (John) on 7 Nov 2009 19:40 In message <OaWOX88XKHA.1372(a)TK2MSFTNGP02.phx.gbl>, Richard <richard(a)avbtab.org> writes: > >> "J. P. Gilliver (John)" <G6JPG(a)soft255.demon.co.uk> wrote in message >> news:Ta5FQGaKTB5KFwoY(a)soft255.demon.co.uk... >> I know one way to join files: in a command box, >> >> copy /b filea+fileb filec >> >> . However, if filea is huge, this takes a noticeable time, because >> the entirety of filea is copied to filec (followed by fileb, >> obviously). I know with text files, you can just append things to >> another file - e. g. >> >> dir >> filea >> >> will I think append a directory listing to filea, or >> >> type fileb >> filea >> >> will append fileb to filea - but only if it's a text file. >> >> Anyone know how to concatenate arbitrary files, without involving a third >> file? > >To append fileB to fileA: > >copy /b fileA+fileB fileA > >FWIW. --Richard > > > Won't that still go through the motions of copying every byte of fileA, even if it's putting the results back in the same place? -- J. P. Gilliver. UMRA: 1960/<1985 MB++G.5AL-IS-P--Ch++(p)Ar(a)T0H+Sh0!:`)DNAf ** http://www.soft255.demon.co.uk/G6JPG-PC/JPGminPC.htm for ludicrously outdated thoughts on PCs. ** Archduke Ferdinand found alive - First World War a mistake!
From: Jim on 8 Nov 2009 08:45 I've been following this correspondence with interest, since, for a reason which escapes me now, I used to append one text file to another back in the days of DOS. However, one thing escapes me : apart from text files (under which term I include program source code and anything else in text), what would be the point of appending one file to another? Jim
From: Richard on 9 Nov 2009 12:12
>>> "J. P. Gilliver (John)" <G6JPG(a)soft255.demon.co.uk> wrote in message >>> news:Ta5FQGaKTB5KFwoY(a)soft255.demon.co.uk... >>> I know one way to join files: in a command box, >>> >>> copy /b filea+fileb filec >>> >>> . However, if filea is huge, this takes a noticeable time, because >>> the entirety of filea is copied to filec (followed by fileb, >>> obviously). I know with text files, you can just append things to >>> another file - e. g. >>> >>> dir >> filea >>> >>> will I think append a directory listing to filea, or >>> >>> type fileb >> filea >>> >>> will append fileb to filea - but only if it's a text file. >>> >>> Anyone know how to concatenate arbitrary files, without involving a >>> third file? >> >> In message <OaWOX88XKHA.1372(a)TK2MSFTNGP02.phx.gbl>, Richard >> <richard(a)avbtab.org> writes: >> >> To append fileB to fileA: >> >> copy /b fileA+fileB fileA >> >> FWIW. --Richard >> >> >> > "J. P. Gilliver (John)" <G6JPG(a)soft255.demon.co.uk> wrote in message > news:H+xAZsK6Nh9KFwI$@soft255.demon.co.uk... > > Won't that still go through the motions of copying every byte of fileA, > even if it's putting the results back in the same place? Hi again John, (Actually, I used such small test files it was too fast to tell. :) Here's the output of my 2 tests: C:\>copy /a test1.txt+test2.txt test1.txt test1.txt test2.txt 1 file(s) copied. C:\>type test1.txt This is test1... This is test2... C:\>copy /a test1.txt+test2.txt+test3.txt test1.txt test1.txt test2.txt test3.txt 1 file(s) copied. C:\>type test1.txt This is test1... This is test2... This is test2... This is test3... Note that it says only "1 file(s) copied." (We need bigger guns... :) Made a copy of a 120MB exe file as trial1.exe (took more than 2 seconds) Made a copy of a 5MB exe file as trial2.exe (took less than a second) C:\>copy /b trial1.exe+trial2.exe trial1.exe took less than a second to append 5MB to 120MB file to get 125MB Deleted both trial*.exe files. Copied 120MB exe file as trial1.exe again Copied 5MB exe file as trial2.exe again C:\>copy /b trial2.exe+trial1.exe trial2.exe took more than 2 seconds to append 120MB file to 5MB file to get 125MB Deleted both trial*.exe files. That proves that when appending the small to the large file, the large file was not re-copied into itself, but the 2nd file was only added on the end. HTH. (Hope This Helps. :) --Richard - - - Special Veteran's Day Remembrance http://www.avbtab.org/rc/veterans.htm |