Loading text files as binary
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Hey, I'm trying to make a simple file archiving utility (bundling several files into one) similar to tar/winzip, without any compression. I tried loading text files with std::ifstream::binary, but this doesn't appear to work correctly. It is creating a 36k file from two 1k files. I don't think it is a problem of the rest of my code. So can you load text files in this way? If not, what else should I try? Thanks.
That should work, alothough my guess is that you're using the stream operators, which will still produce formatted output - even if the file was open in binary.
With out seeing the rest of your code, this is only a guess, but try this:
For more information, click me.
HTH
With out seeing the rest of your code, this is only a guess, but try this:
int myInt = 123456;std::ofstream file("C:/file.zip", std::ios::binary);//file << myInt; //This will write "123456" to the filefile.write(reinterpret_cast<const char *>(&myInt), sizeof(myInt)); //This will write the int as it appears in memory, i.e. ' @Ô☺' (only four characters long)For more information, click me.
HTH
Something like this:
// include a gazillion appropriate headersusing namespace std;void tar(vector<string> infiles, string outfile) { ofstream out(outfile, ios::binary); for (vector<string>::iterator it = infiles.begin(); it != infiles.end(); ++i) { ifstream in(infile, ios::binary); // Write some other data to "out" to indicate file length, or something copy(istream_iterator<char>(in), istream_iterator<char>(), ostream_iterator(out)); }}
Actually Zahlman, as Fruny pointed out, using a std::istream_iterator will skip white space, so you should infact use a std::istreambuf_iterator
Wow, I corrected Zahlman [grin] me does happy dance
Wow, I corrected Zahlman [grin] me does happy dance
Quote:Original post by desertcube
Actually Zahlman, as Fruny pointed out, using a std::istream_iterator will skip white space, so you should infact use a std::istreambuf_iterator
Wow, I corrected Zahlman [grin] me does happy dance
Well the fact of the matter is if he is just copying a a whole files unmodified there is a much more efficient method than using stream/stream buffer iterators:
#include <string>#include <fstream>inline const char* get_str(const char* s) { return s;}template < typename Traits, typename Alloc >inline const char* get_str(const std::basic_string<char, Traits, Alloc>& s) { return s.c_str();}template < typename InputIterator, typename CharT, typename Traits >void tar(InputIterator first, InputIterator last, std::basic_ofstream<CharT, Traits>& out) { std::basic_ifstream<CharT, Traits> in; for(; first != last; ++first) { in.open(get_str(*first)); // ... out << in.rdbuf(); // ... in.close(); in.clear(); }}#include <cstddef>int main() { const char* filenames[] = { "foo.txt", "bar.txt", "foobar.txt" }; const std::size_t N = sizeof(filenames) / sizeof(const char*); std::ofstream out(...); tar(filenames, filenames + N, out);}[Edited by - snk_kid on June 19, 2005 7:07:43 AM]
Quote:Original post by silverphyre673
Hey, I'm trying to make a simple file archiving utility (bundling several files into one) similar to tar/winzip, without any compression.
SimpleArchive [grin]
Why doust thau hate thy humble C?! [depressed]
/* This function loads a file into a buffer as binary. */char *fLoadBinary(char chrFileName[], int intLen){ char *bufInfo; FILE *f; bufInfo = malloc(intLen); f = fopen(chrFileName, "rb"); fread(bufInfo,intLen,1,f); fclose(f); return bufInfo;}Quote:Original post by desertcube
Actually Zahlman, as Fruny pointed out, using a std::istream_iterator will skip white space, so you should infact use a std::istreambuf_iterator
Wow, I corrected Zahlman [grin] me does happy dance
Even reading characters? D: That's not so useful then.
But yes, the rdbuf mapping is teh win.
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