split command: need some help

[dharanitharan]

hi friends,
i need some clarifications in "SPLIT" command.... hope all are know this command is used to split the specified file in the specified size.... i want to split a video file of size 300 MB into 3 parts of size 100 MB each.... wat s d split command i ve to use

[oz]

Check this man page for detailed instructions and options for splitting your file:

Linux Command Directory: split

[Rubberman]

The problem with the split command is that it is intended for text files, such as logs. Myself, I usually use the Windows QuickPar 0.9.1 under Wine for splitting files. It also generates recovery par files which can go along with the file parts to reconstitute the original file. Another tool is rar of which there is a Linux version that works quite well.

[dharanitharan]

rar is available in linux also va... but whenever i try 2 open a rar file it shows a error message"Archive type not supported"

[Rubberman]

What version of rar are you running? Also, how are you invoking it? Since you are using it to create an archive, you should not be getting this error.

[Rubberman]

BTW, here is the source code for a binary file splitter I wrote for my personal tool box a long time ago. I just compiled and ran it on my CentOS linux system without any problems. Save it to a file named bsplit.c and to build it, go to the directory you save the file in and execute the command: make bsplit

#include <stdio.h>
#include <errno.h>
#include <limits.h>
#include <malloc.h>

void usage( void )
{
    fprintf(stderr, "usage: bsplit -i<fname> -o<root> [-s<size>]\n"
                    "       -i<fname>: input file name\n"
                    "       -o<root>: output segment root name\n"
                    "       -s<size>: maximum size of each output segment\n");
}

/* Returns errno */
int split_file( const char* ifname, const char* ofroot, unsigned int segsize )
{
    char ofname[PATH_MAX + 1];
    FILE *ifp, *ofp;
    unsigned segnum = 0;
    size_t bytes_read;
    size_t bytes_written;
    void* iobuffer;
    int retval = 0;

    iobuffer = (void*)malloc((size_t)segsize);
    if (iobuffer == NULL)
    {
        retval = ENOMEM;
    }

    ifp = fopen(ifname, "r");
    if (ifp == NULL)
    {
        return errno;
    }

    do
    {
        errno = retval = 0;
        sprintf(ofname, "%s.%u", ofroot, segnum);
        ofp = fopen(ofname, "w");
        if (ofp == NULL)
        {
            retval = errno;
        }
        else
        {
            bytes_read = fread(iobuffer, (size_t)1, (size_t)segsize, ifp);
            if (errno)
            {
                retval = errno;
            }
            else if (bytes_read > 0)
            {
                bytes_written = fwrite(iobuffer, (size_t)1, bytes_read, ofp);
                retval = errno;
            }
        }
        fclose(ofp);
        ++segnum;
    }
    while (!retval && !feof(ifp));
    fclose(ifp);

    return retval;
}

int main( int argc, const char** argv )
{
    const char* ifname = NULL;
    const char* ofroot = NULL;
    int segsize = -1;
    int i;

    if (argc < 3 || argc > 4)
    {
        usage();
        return -1;
    }
    for (i = 1; i < argc; i++)
    {
        if (strncmp(argv[i], "-i", 2) == 0)
        {
            if (ifname != NULL)
            {
                usage();
                return 1;
            }
            ifname = argv[i] + 2;
        }
        else if (strncmp(argv[i], "-o", 2) == 0)
        {
            if (ofroot != NULL)
            {
                usage();
                return 2;
            }
            ofroot = argv[i] + 2;
        }
        else if (strncmp(argv[i], "-s", 2) == 0)
        {
            if (segsize != -1)
            {
                usage();
                return 3;
            }
            segsize = atoi(argv[i] + 2);
        }
        else
        {
            usage();
            return 4;
        }
    }

    if (segsize <= 0)
    {
        segsize = 65535;
    }

    i = split_file( ifname, ofroot, (unsigned int)segsize );
    if (i)
    {
        fprintf(stderr, "bsplit: errno %d: %s\n", i, strerror(i));
    }
    return i;
}

[dharanitharan]

thanks a lot

[ghostdog74]

The problem with the split command is that it is intended for text files,

the -b option specifies bytes , which can be used for binary files.

[dharanitharan]

we cant use it for multimedia files ah

[Rubberman]

My bsplit command will work on multimedia files, or any binary data. That's what I wrote it to do. You can simply cat the parts back together as necessary and you will get the original file back.