lua - Binary Code to String -

i playing feed beast , create network. can send binary codes 1 computer another. method binary code out of string following:

function tobinstring(s)   bytes = {string.byte(s,i,string.len(s))}   binary = ""    i,number in ipairs(bytes)     c = 0      while(number>0)       binary = (number%2)..binary       number = number - (number%2)       number = number/2       c = c+1     end      while(c<8)       binary = "0"..binary       c = c+1     end   end    return binary end  function tobin(s)   binary = tobinstring(s)       ret = {}   c = 1    i=1,string.len(binary)     char = string.sub(binary,i,i)      if(tonumber(char)==0)       ret[c] = 0       c = c+1     elseif(tonumber(char)==1)       ret[c] = 1       c = c+1     elseif(tonumber(char))       print("error: expected \'0\' or \'1\' got \'",char,"\'.")     end   end    return ret end 

how can string used in string.byte(...)?

here 1 possibility:

function tobinandback(s)   local bin = tobin(s)   local r = {}   i=1,#bin,8     local n = 0     j=0,7       n = n + (2^(7-j)) * bin[i+j]     end     r[#r+1] = n   end   return string.char(unpack(r)):reverse() end 

the reverse @ end needed because encode strings in reverse in tobinstring. also, had replace line: bytes = {string.byte(s,i,string.len(s))} bytes = {string.byte(s,1,-1)} make code work.

note using unpack() limits size of string can decoded. if want decode arbitrarily long strings, can replace last line (return string.char(unpack(r)):reverse()) this:

for i=1,#r   r[i] = string.char(r[i]) end return table.concat(r):reverse()