随手写的,可能有错误,你参考一下

程序代码:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main()
{
    // 输入信息
    const char* filename = "gen_hapmap";
    const size_t N = 10000;
    int retval = 1; // 返回值
    if( N == 0 )
    {
        printf( "parameter error.\n" );
        goto error001;
    }
    // 打开输入文件
    FILE* fin = fopen( filename, "rt" );
    if( !fin )
    {
        printf( "Failed to open file named \"%s\".\n", filename );
        goto error001;
    }
    // 计算需要分成几段
    unsigned part = 0;
    {
        unsigned maxchrnum = 0;
        unsigned chrnum = 0;
        for( char line[N+1]; fgets(line,N+1,fin); )
        {
            chrnum += strlen(line);
            if( strchr(line,'\n') )
            {
                if( chrnum-1 > maxchrnum )
                    maxchrnum = chrnum-1;
                chrnum = 0;
            }
        }
        if( chrnum > maxchrnum ) // 最末一行可能没有回车符
            maxchrnum = chrnum;
        if( ferror(fin) )
        {
            printf( "Failed to read file named \"%s\".\n", filename );
            goto error002;
        }
        rewind( fin );
        part = (maxchrnum+N-1)/N;
    }
    // 创建输出文件
    FILE** fout = (FILE**)calloc( part, sizeof(FILE*) );
    if( !fout )
    {
        printf( "Failed to call malloc function.\n" );
        goto error002;
    }
    for( unsigned i=0; i!=part; ++i )
    {
        char fileout[260];
        sprintf( fileout, "%s(%u-%u)", filename, i*N, i*N+N-1 );
        fout[i] = fopen( fileout, "wt" );
        if( !fout[i] )
        {
            printf( "Failed to create file named \"%s\".\n", fileout );
            goto error003;
        }
    }
    // 文件垂直分割
    unsigned col = 0;
    for( char line[N+1+1]; fgets(line,N+1,fin); )
    {
        size_t len = strlen(line);
        if( line[len-1] == '\n' )
        {
            if( len != 1 ) // 只截得回车符
            {
                if( fputs(line,fout[col]) < 0 )
                {
                    printf( "Failed to write file.\n" );
                    goto error003;
                }
                ++col;
            }
            for( ; col!=part; ++col )
            {
                if( fputs("\n",fout[col]) < 0 )
                {
                    printf( "Failed to write file.\n" );
                    goto error003;
                }
            }
            col = 0;
        }
        else
        {
            if( len != N )
            {
                if( !feof(fin) )
                {
                    printf( "Failed to read \"%s\"\n", filename );
                    goto error002;
                }
                if( fputs(line,fout[col]) < 0 )
                {
                    printf( "Failed to write file.\n" );
                    goto error003;
                }
                break;
            }
            line[len] = '\n';
            line[len+1] = '\0';
            if( fputs(line,fout[col]) < 0 )
            {
                printf( "Failed to write file.\n" );
                goto error003;
            }
            ++col;
        }
    }
    if( ferror(fin) )
    {
        printf( "Failed to read \"%s\"\n", filename );
        goto error003;
    }
    retval = 0;
    // 资源释放
error003:
    for( unsigned i=0; i!=part && fout[i]; ++i )
    {
        fclose( fout[i] );
        if( retval != 0 )
        {
            char fileout[260];
            sprintf( fileout, "%s(%u-%u)", filename, i*N, i*N+N-1 );
            remove( fileout );
        }
    }
    free( fout );
error002:
    fclose( fin );
error001:
    return retval;
}