status=fsplit(file,mb)

function status=fsplit(file,mb)

%Program to split a large file to smaller files
%
%Usage
%
%       fsplit(file,mb)
%
%   Simple function that splits file to smaller files, each of size mb (in megabytes)
%   Named filename1.spt , filename2.spt , filename3.spt, etc
%   Each file containing mb megabytes of file
%
%   Can be used to split large raw data files (or any file) for transfer.
%
%   SEE ALSO fappend, mfappend, uimfappend

%Suresh Joel - April 10,2003

switch(nargin)
case 0
   [filename pathname]=uigetfile('*.*','File to append to');
   file=strcat(pathname,filename);
   mb=str2num(char(inputdlg('Size of files that you want to create')));
case 1
   mb=str2num(char(inputdlg('Size of files that you want to create')));
case 2
   %do nothing
end

if(~exist(file))
    status=-1;
    error(strcat('Cant find source file -',file));
end

fidin=fopen(file,'r');
fseek(fidin,0,'eof');
pos=ftell(fidin);
totmb=pos/(1024*1024);
if totmb<mb, %If file size is less than mb, no need to write new file
    disp(strcat('File size is less than :',num2str(mb),'Mb'));
    disp('No spt file written');
    return;
end;
fseek(fidin,0,'bof');
mbcount=0;
i=1;
hw=waitbar(0,'Please wait till file is split ...');
prei='';
while(mbcount<totmb),
    n=0;
    %Sequential file naming
    nprei=length(num2str(round(totmb/mb)))-length(num2str(round(i)));
    for ii=1:nprei, prei(1,ii)='0'; end;
    fidout=fopen(strcat(file,prei,num2str(i),'.spt'),'w');
    prei='';
    %Write mb bytes into new file
    if mb>1, rmb=1; else rmb=mb; end;
    while(n<mb),
        c=fread(fidin,1024*1024*rmb,'uchar');
        if isempty(c), break; end; %if c is empty (reached end of file) break out of loop
        fwrite(fidout,c,'uchar');
        n=n+1;
        if(mb-n)>=1,rmb=1; else rmb=mb-n;end;
    end;
    fclose(fidout);
    mbcount=mbcount+mb;
    i=i+1;
    waitbar(mbcount/totmb,hw);
end;
fclose(fidin);
status=0;
close(hw);