First version of the BDIO package in julia

Manifest.toml

+# This file is machine-generated - editing it directly is not advised
+
+[[Base64]]
+uuid = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"
+
+[[BinDeps]]
+deps = ["Compat", "Libdl", "SHA", "URIParser"]
+git-tree-sha1 = "12093ca6cdd0ee547c39b1870e0c9c3f154d9ca9"
+uuid = "9e28174c-4ba2-5203-b857-d8d62c4213ee"
+version = "0.8.10"
+
+[[BinaryProvider]]
+deps = ["Libdl", "Logging", "SHA"]
+git-tree-sha1 = "c7361ce8a2129f20b0e05a89f7070820cfed6648"
+uuid = "b99e7846-7c00-51b0-8f62-c81ae34c0232"
+version = "0.5.6"
+
+[[Compat]]
+deps = ["Base64", "Dates", "DelimitedFiles", "Distributed", "InteractiveUtils", "LibGit2", "Libdl", "LinearAlgebra", "Markdown", "Mmap", "Pkg", "Printf", "REPL", "Random", "Serialization", "SharedArrays", "Sockets", "SparseArrays", "Statistics", "Test", "UUIDs", "Unicode"]
+git-tree-sha1 = "ed2c4abadf84c53d9e58510b5fc48912c2336fbb"
+uuid = "34da2185-b29b-5c13-b0c7-acf172513d20"
+version = "2.2.0"
+
+[[Dates]]
+deps = ["Printf"]
+uuid = "ade2ca70-3891-5945-98fb-dc099432e06a"
+
+[[DelimitedFiles]]
+deps = ["Mmap"]
+uuid = "8bb1440f-4735-579b-a4ab-409b98df4dab"
+
+[[Distributed]]
+deps = ["Random", "Serialization", "Sockets"]
+uuid = "8ba89e20-285c-5b6f-9357-94700520ee1b"
+
+[[DocStringExtensions]]
+deps = ["LibGit2", "Markdown", "Pkg", "Test"]
+git-tree-sha1 = "88bb0edb352b16608036faadcc071adda068582a"
+uuid = "ffbed154-4ef7-542d-bbb7-c09d3a79fcae"
+version = "0.8.1"
+
+[[Documenter]]
+deps = ["Base64", "DocStringExtensions", "InteractiveUtils", "JSON", "LibGit2", "Logging", "Markdown", "REPL", "Test", "Unicode"]
+git-tree-sha1 = "d45c163c7a3ae293c15361acc52882c0f853f97c"
+uuid = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
+version = "0.23.4"
+
+[[InteractiveUtils]]
+deps = ["Markdown"]
+uuid = "b77e0a4c-d291-57a0-90e8-8db25a27a240"
+
+[[JSON]]
+deps = ["Dates", "Mmap", "Parsers", "Unicode"]
+git-tree-sha1 = "b34d7cef7b337321e97d22242c3c2b91f476748e"
+uuid = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"
+version = "0.21.0"
+
+[[LibGit2]]
+uuid = "76f85450-5226-5b5a-8eaa-529ad045b433"
+
+[[Libdl]]
+uuid = "8f399da3-3557-5675-b5ff-fb832c97cbdb"
+
+[[LinearAlgebra]]
+deps = ["Libdl"]
+uuid = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
+
+[[Logging]]
+uuid = "56ddb016-857b-54e1-b83d-db4d58db5568"
+
+[[Markdown]]
+deps = ["Base64"]
+uuid = "d6f4376e-aef5-505a-96c1-9c027394607a"
+
+[[Mmap]]
+uuid = "a63ad114-7e13-5084-954f-fe012c677804"
+
+[[Nettle]]
+deps = ["BinDeps", "BinaryProvider", "Libdl", "Test"]
+git-tree-sha1 = "f57e8e907faab4f55f9f164313a633509ac83e2c"
+uuid = "49dea1ee-f6fa-5aa6-9a11-8816cee7d4b9"
+version = "0.4.0"
+
+[[Parsers]]
+deps = ["Dates", "Test"]
+git-tree-sha1 = "ef0af6c8601db18c282d092ccbd2f01f3f0cd70b"
+uuid = "69de0a69-1ddd-5017-9359-2bf0b02dc9f0"
+version = "0.3.7"
+
+[[Pkg]]
+deps = ["Dates", "LibGit2", "Markdown", "Printf", "REPL", "Random", "SHA", "UUIDs"]
+uuid = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
+
+[[Printf]]
+deps = ["Unicode"]
+uuid = "de0858da-6303-5e67-8744-51eddeeeb8d7"
+
+[[REPL]]
+deps = ["InteractiveUtils", "Markdown", "Sockets"]
+uuid = "3fa0cd96-eef1-5676-8a61-b3b8758bbffb"
+
+[[Random]]
+deps = ["Serialization"]
+uuid = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
+
+[[SHA]]
+uuid = "ea8e919c-243c-51af-8825-aaa63cd721ce"
+
+[[Serialization]]
+uuid = "9e88b42a-f829-5b0c-bbe9-9e923198166b"
+
+[[SharedArrays]]
+deps = ["Distributed", "Mmap", "Random", "Serialization"]
+uuid = "1a1011a3-84de-559e-8e89-a11a2f7dc383"
+
+[[Sockets]]
+uuid = "6462fe0b-24de-5631-8697-dd941f90decc"
+
+[[SparseArrays]]
+deps = ["LinearAlgebra", "Random"]
+uuid = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
+
+[[Statistics]]
+deps = ["LinearAlgebra", "SparseArrays"]
+uuid = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
+
+[[Test]]
+deps = ["Distributed", "InteractiveUtils", "Logging", "Random"]
+uuid = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+
+[[URIParser]]
+deps = ["Test", "Unicode"]
+git-tree-sha1 = "6ddf8244220dfda2f17539fa8c9de20d6c575b69"
+uuid = "30578b45-9adc-5946-b283-645ec420af67"
+version = "0.4.0"
+
+[[UUIDs]]
+deps = ["Random", "SHA"]
+uuid = "cf7118a7-6976-5b1a-9a39-7adc72f591a4"
+
+[[Unicode]]
+uuid = "4ec0a83e-493e-50e2-b9ac-8f72acf5a8f5"

Project.toml

+name = "BDIO"
+uuid = "375f315e-f2c4-11e9-2ef9-134f02f79e27"
+authors = ["Alberto Ramos <alberto.ramos@desy.de>"]
+version = "0.1.0"
+
+[deps]
+Documenter = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
+Nettle = "49dea1ee-f6fa-5aa6-9a11-8816cee7d4b9"

docs/make.jl

+using Documenter, BDIO
+
+makedocs(modules=[BDIO], doctest=true)
+
+deploydocs(deps   = Deps.pip("mkdocs", "python-markdown-math"),
+           repo = "github.com/GITHUBNAME/GITHUBREPO.git",
+           julia  = "1.1.1",
+           osname = "FreeBSD")
+

docs/src/index.md

+# BDIO in Julia
+
+This package provides an interface to read/write
+[BDIO](http://bdio.org/) files in Julia.
+
+## Externally callable functions
+
+### Openning `BDIO` files
+
+```@docs
+BDIO.BDIO_open
+```
+
+### Writing data to `BDIO` files
+
+```@docs
+BDIO.BDIO_start_record!
+BDIO.BDIO_write!
+BDIO.BDIO_write_hash!
+```
+
+### Reading data from `BDIO` files
+
+```@docs
+BDIO.BDIO_read
+BDIO.BDIO_seek!
+```
+
+### Obtaining information about `BDIO` records
+
+```@docs
+BDIO.BDIO_get_uinfo
+BDIO.BDIO_get_len
+BDIO.BDIO_get_fmt
+```
+
+## Index
+
+```@index
+```

src/BDIO.jl

+module BDIO
+
+import Nettle
+export BDIO_BIN_GENERIC, BDIO_ASC_EXEC, BDIO_BIN_INT32BE,
+    BDIO_BIN_INT32LE, BDIO_BIN_INT64BE, BDIO_BIN_INT64LE,
+    BDIO_BIN_F32BE, BDIO_BIN_F32LE, BDIO_BIN_F64BE, BDIO_BIN_F64LE,
+    BDIO_ASC_GENERIC, BDIO_ASC_XML, BDIO_BIN_INT32, BDIO_BIN_INT64,
+    BDIO_BIN_F32, BDIO_BIN_F64 
+
+export BDIO, BDIO_open, BDIO_start_record!, BDIO_write_hash!,
+    BDIO_write!, BDIO_seek!, BDIO_get_len, BDIO_get_fmt,
+    BDIO_get_uinfo, BDIO_read
+
+const BDIO_R_MODE    = 0
+const BDIO_W_MODE    = 1
+const BDIO_A_MODE    = 2
+const BDIO_D_MODE    = 3
+const MAXFNAME       = 4096
+const BDIO_SHORT_LEN = 256
+const BDIO_LONG_LEN  = 4096
+const BDIO_MAGIC     = 2147209342
+const BDIO_VERSION   = 1
+const BDIO_R_STATE   = 0
+const BDIO_W_STATE   = 1
+
+
+const BDIO_BIN_GENERIC =   0
+const BDIO_ASC_EXEC    =   1
+const BDIO_BIN_INT32BE =   2
+const BDIO_BIN_INT32LE =   3
+const BDIO_BIN_INT64BE =   4
+const BDIO_BIN_INT64LE =   5
+const BDIO_BIN_F32BE   =   6
+const BDIO_BIN_F32LE   =   7
+const BDIO_BIN_F64BE   =   8
+const BDIO_BIN_F64LE   =   9
+const BDIO_ASC_GENERIC =  10
+const BDIO_ASC_XML     =  11
+const BDIO_BIN_INT32   = 240
+const BDIO_BIN_INT64   = 241
+const BDIO_BIN_F32     = 242
+const BDIO_BIN_F64     = 243
+
+const BDIO_HASH_MAGIC_S = 1515784845
+
+user = "                                                                                                                                                                                                                                                               "
+host = "                                                                                                                                                                                                                                                               "
+
+mutable struct Record
+    ishdr::Bool
+    islong::Bool
+
+    # Record length, start, end
+    rlen::Int64 
+    rpos::Int64
+    rend::Int64
+
+    rfmt::Int32
+    ruinfo::Int8
+
+    hsh::Nettle.Hasher    
+end
+
+mutable struct BDIOstream
+    io::IO
+    ipt::Int64
+    
+    imode::Int32
+    istate::Int32
+    rwpos::Int64
+    
+    lendian::Bool
+
+    user::String
+    host::String
+    created::Int32
+    modified::Int32
+    info::String
+
+    rdate::Int64
+    
+    records::Array{Record,1}
+end
+
+"""
+Set user name globally for writing BDIO files. 
+
+### Example
+BDIO_set_user("alberto")
+"""
+function BDIO_set_user(us::String)
+    global user = SubString(us*user, 1, 255)
+    return true
+end
+
+"""
+Set host machine globally for writing BDIO files. 
+
+### Example
+BDIO_set_host("HLRN")
+"""
+function BDIO_set_host(us::String)
+    global host = SubString(us*host, 1, 255)
+    return true
+end
+
+
+function BDIOstream(fname::String, mode::String, protocol_info::String="\0")
+
+    md::Int32 = 0
+    if (mode == "w")
+        if (isfile(fname))
+            error("File "*strip(fname)*" already exists")
+        end
+        io = open(fname, "w+")
+        md = BDIO_W_MODE
+    elseif (mode == "r")
+        io = open(fname, "r")
+        md = BDIO_R_MODE
+    elseif (mode == "a")
+        io = open(fname, "a+")
+        md = BDIO_A_MODE
+    elseif (mode == "d")
+        rm(fnme, force=true)
+        io = open(fname, "w+")
+        md = BDIO_D_MODE
+    else
+        error("Incorrect mode")
+    end
+    rcs = similar(Array{Record,1},0)
+
+    lend::Bool = true
+    if (Base.ENDIAN_BOM == 0x04030201)
+        lend = true
+    elseif (Base.ENDIAN_BOM == 0x01020304)
+        lend = false
+    else
+        error("Wrong endianness")
+    end
+    if (!lend)
+        error("Current version only support Little Endian Machines")
+    end
+    
+    return BDIOstream(io,1,md,0,0,lend,user,host,
+                floor(Int32, time()), floor(Int32, time()), protocol_info, 0, rcs)
+end
+    
+"""
+Opens a BDIO file and returns the BDIO handle. The file can be opened in several modes:
+- Write mode ("w"): The file is created and a header written. If the file exists an error is printed.
+- Write mode ("d"): The file is created and a header written. If the file exists it is overwritten.
+- Write mode ("a"): The file is created if it does not exist, or opened for appending if the file exists.
+- Write mode ("r"): The file is opened for reading.
+
+## Arguments
+- `fname`: File name
+- `mode`:  The mode in which the file is opened. See above.
+- `protocol_info`: Only used when the file is created (i.e. "w" mode) and labels the file. 
+
+## Examples
+```julia-repl
+julia> fb = BDIO_open("new_file.bdio", "w", "Test file")
+```
+
+## Returns
+A BDIOstream type.
+
+"""
+function BDIO_open(fname::String, mode::String, protocol_info::String="")
+
+    fb = BDIOstream(fname,mode)
+    fb.info = protocol_info
+    fb.user = user
+    fb.host = host
+    
+    if (mode == "w")
+        fb.created  = floor(Int32, time())
+        fb.modified = floor(Int32, time())
+        BDIO_write_header!(fb)
+    elseif (mode == "r")
+        BDIO_parse!(fb)
+        fb.ipt = 1
+    elseif (mode == "a")
+        BDIO_parse!(fb)
+        fb.ipt = length(fb.records)
+    elseif (mode == "d")
+        BDIO_parse!(fb)
+        fb.ipt = length(fb.records)
+    else
+        error("Incorrect mode")
+    end
+
+    return fb
+end
+
+function BDIO_write_header!(fb::BDIOstream)
+
+    if (fb.imode == BDIO_R_MODE)
+        error("Attemp to write in READ mode")
+    end
+    
+    ihdr::Int32 = BDIO_MAGIC
+    write(fb.io, ihdr)
+
+    mark(fb.io)
+    ill::Int16  = 0
+    write(fb.io, ill)
+
+    iv::Int16 = 1
+    write(fb.io, iv)
+    ist::Int64 = position(fb.io)
+
+    i4::Int32 = 0
+    write(fb.io, i4)
+
+    hcr::Int64 = position(fb.io)
+    write(fb.io, fb.created)
+    fb.rdate   = position(fb.io)
+    write(fb.io, fb.modified)
+
+    write(fb.io, user*"\0")
+    hlu::Int64 = position(fb.io)
+    write(fb.io, user*"\0")
+    write(fb.io, host*"\0")
+    hlh::Int64 = position(fb.io)
+    write(fb.io, host*"\0")
+
+    write(fb.io, fb.info*"\0")
+    ind::Int64 = position(fb.io)
+
+    ill = Int16(ind-ist)
+    reset(fb.io)
+    write(fb.io, ill)
+    flush(fb.io)
+
+    hsh = Nettle.Hasher("md5")
+    new = Record(true,false,Int64(ill),ist,ind,0,0,hsh)
+    push!(fb.records, new)
+    fb.ipt += 1
+    
+    return true
+end
+
+"""
+Start a new BDIO record at the end of the file. Currently the supported formats are 
+- `BDIO_BIN_GENERIC`: Generic binary data
+- `BDIO_ASC_EXEC`: ASCII Executable (i.e. `sh` script)
+- `BDIO_BIN_INT32BE`: 32-bit integer in Big Endian format 
+- `BDIO_BIN_INT32LE`: 32-bit integer in Little Endian format 
+- `BDIO_BIN_INT64BE`: 64-bit integer in Big Endian format    
+- `BDIO_BIN_INT64LE`: 64-bit integer in Little Endian format 
+- `BDIO_BIN_F32BE`: 32-bit float in Big Endian format    
+- `BDIO_BIN_F32LE`: 32-bit float in Little Endian format   
+- `BDIO_BIN_F64BE`: 64-bit float in Big Endian format      
+- `BDIO_BIN_F64LE`: 64-bit float in Little Endian format     
+- `BDIO_ASC_GENERIC`: ASCII text file
+- `BDIO_ASC_XML`: Plain XML data
+
+## Arguments
+- `fb`: A BDIOstream type. It must be associated with a file in either `w` or `a` mode
+- `ifmt`: Format (see above).
+- `iuinfo`: Integer in the range 0-15. A user specified label to help indentifying the record
+- `long` (optional): If true create a long record. To store more than 1048575 bytes of data (``\\approx 1\\, {\\rm MB}``), a long record is required. Default value of `false`.
+
+## Examples
+```julia-repl
+julia> fb = BDIO_open("new_file.bdio", "w", "Test file")
+julia> BDIO_start_record!(fb, BDIO.BDIO_BIN_F32, 2)
+```
+
+"""
+function BDIO_start_record!(fb::BDIOstream, ifmt, iuinfo, long::Bool = false)
+
+    if (fb.imode == BDIO_R_MODE)
+        error("Attemp to write in READ mode")
+    end
+    
+    seekend(fb.io)
+
+    shdr::Int32 = 0
+    if long
+        shdr = 0b1001
+    else
+        shdr = 0b1
+    end
+
+    shdr = shdr | ifmt<<4
+    shdr = shdr | iuinfo<<8
+
+    write(fb.io,shdr)
+    if long
+        zero::Int32 = 0
+        write(fb.io,zero)
+    end
+    ist::Int64 = position(fb.io)
+    
+    hsh = Nettle.Hasher("md5")
+    new = Record(false,long,Int64(0),ist,ist,Int32(ifmt),Int8(iuinfo),hsh)
+    push!(fb.records, new)
+    fb.ipt += 1
+    flush(fb.io)
+    
+    return true
+end
+
+"""
+Write `data` to BDIO file to the end of the last record. 
+
+## Arguments
+- `fb`: A BDIOstream type. It must be associated with a file in either `w` or `a` mode.
+- `data`: Data to write to file. 
+- `hash` (optional): Bool. If true, data will be checksummed before writtento file. The hash can be stored in a BDIO record by calling `BDIO_write_hash(...)`
+
+## Examples
+```julia-repl
+julia> # Write 1000 normal random numbers to file `randoms.bdio`
+julia> fb = BDIO_open("randoms.bdio", "w", "File with random numbers")
+julia> BDIO_start_record!(fb, BDIO.BDIO_BIN_F32, 2)
+julia> BDIO_write!(fb, randn(1000))
+```
+"""
+function BDIO_write!(fb,data,hash::Bool=true)
+
+    if (fb.imode == BDIO_R_MODE)
+        error("Attemp to write in READ mode")
+    end
+    
+    ir = length(fb.records)
+    fb.records[ir].rlen += sizeof(data)
+    fb.records[ir].rend += sizeof(data)
+    update_length(fb, ir)
+
+    seekend(fb.io)
+    write(fb.io, data)
+    flush(fb.io)
+    if hash
+        Nettle.update!(fb.records[ir].hsh, data)
+    end
+    update_hdrinfo!(fb)
+    
+    return true
+end
+
+"""
+Write the `MD5` checksum of the actual record as a new record.
+
+## Arguments
+- `fb`: A BDIOstream type. It must be associated with a file in either `w` or `a` mode.
+
+## Examples
+```julia-repl
+julia> # Write 1000 normal random numbers to file `randoms.bdio` with checksum
+julia> fb = BDIO_open("randoms.bdio", "w", "File with random numbers")
+julia> BDIO_start_record!(fb, BDIO.BDIO_BIN_F32, 2)
+julia> BDIO_write!(fb, randn(1000))
+julia> BDIO_write_hash!(fb)
+```
+"""
+function BDIO_write_hash!(fb)
+
+    if (fb.imode == BDIO_R_MODE)
+        error("Attemp to write in READ mode")
+    end
+    
+    ir = length(fb.records)
+    BDIO_start_record!(fb,BDIO_BIN_GENERIC,7)
+    i4::Int32 = BDIO_HASH_MAGIC_S
+    BDIO_write!(fb, i4, false)
+    BDIO_write!(fb, Nettle.digest!(fb.records[ir].hsh))
+    
+end
+    
+function update_length(fb::BDIOstream, ir)
+
+    mark(fb.io)
+    if fb.records[ir].islong
+        seek(fb.io,fb.records[ir].rpos-8)
+        r64 = read(fb.io,Int64)
+        mask64::Int64 = 0b111111111111
+        mask64 = mask64 & r64
+        il64::Int64   = (fb.records[ir].rend - fb.records[ir].rpos)<<12
+        iw64::Int64   = il64 | mask64
+
+        seek(fb.io,fb.records[ir].rpos-8)
+        write(fb.io,iw64)
+    else
+        seek(fb.io,fb.records[ir].rpos-4)
+        r32 = read(fb.io,Int32)
+        mask32::Int32 = 0b111111111111
+        mask32 = mask32 & r32
+        il32::Int32   = Int32((fb.records[ir].rend - fb.records[ir].rpos))<<12
+        iw32::Int32   = il32 | mask32
+
+        seek(fb.io,fb.records[ir].rpos-4)
+        write(fb.io,iw32)
+    end
+    flush(fb.io)
+    reset(fb.io)
+    
+    return
+end
+
+function update_hdrinfo!(fb)
+
+    mark(fb.io)
+    seek(fb.io, fb.rdate)
+    write(fb.io,floor(Int32, time()))
+    
+    flush(fb.io)
+    reset(fb.io)
+
+end
+
+function BDIO_parse!(fb::BDIOstream)
+
+    seekstart(fb.io)
+    ihdr = read(fb.io, Int32)
+    
+    mask32::Int32 = 0b111111111111
+    rlen = Int64(read(fb.io, Int32) & mask32)
+    rpos = position(fb.io)
+    
+    hsh = Nettle.Hasher("md5")
+    il4  = read(fb.io, Int32)
+    idt1 = read(fb.io, Int32)
+    idt2 = read(fb.io, Int32)
+    user = readuntil(fb.io, '\0')
+    user = readuntil(fb.io, '\0')
+    host = readuntil(fb.io, '\0')
+    host = readuntil(fb.io, '\0')
+    info = readuntil(fb.io, '\0')
+    if (ihdr!=BDIO_MAGIC)
+        error("Not a BDIO file")
+    end
+    new  = Record(true,false,rlen,rpos,rpos+rlen,0,0,hsh)
+    push!(fb.records, new)
+    seek(fb.io, rpos+rlen)
+    
+    rlen::Int64 = 0
+    rpos::Int64 = 0
+    while !eof(fb.io)
+        ihdr  = read(fb.io, Int32)
+        ishdr = (mask = 1<<0; ihdr & mask != mask)
+        if ishdr
+            if (ihdr != BDIO_MAGIC)
+                error("Not a BDIO file")
+            end
+            i32::Int32 = read(fb.io, Int32)
+            rlen = Int64(i32 & 0b111111111111)
+            rpos = position(fb.io)
+            new  = Record(true,false,rlen,rpos,rpos+rlen,0,0,hsh)
+        else
+            islong = (mask = 1<<3; ihdr & mask == mask)
+            ifmt::Int32  = (ihdr & 0b11110000)>>>4
+                iuinfo::Int8 = Int8((ihdr & 0b111100000000)>>>8)
+            if islong
+                rpos  = position(fb.io) + 4
+                ihdr2 = read(fb.io, Int32)
+                rlen  = ihdr>>>12 | ihdr2<<32
+            else
+                rpos = position(fb.io)
+                rlen = ihdr>>>12
+            end
+            new  = Record(false,islong,rlen,rpos,rpos+rlen,Int32(ifmt),Int8(iuinfo),hsh)
+        end
+
+        push!(fb.records, new)
+        skip(fb.io, rlen)
+    end
+    fb.ipt = 1
+
+end
+
+"""
+Move the read position backward/forward `icnt` records
+
+## Arguments
+- `fb`: A BDIOstream type. It must be associated with a file.
+- `icnt` (optional): number of records to move forward (if `icnt>0`) or backwards (`icnt<0`). The default value is `+1`.
+
+## Examples
+```julia-repl
+julia> # count number of records in a file.
+julia> fb = BDIO_open("randoms.bdio", "r")
+julia> count = 0
+julia> while BDIO_seek(fb)
+julia>     count += 1
+julia> end
+```
+"""
+function BDIO_seek!(fb::BDIOstream, icnt::Int = 1)
+
+    ipt::Int64 = fb.ipt
+    if (icnt == 0)
+        ipt = 1
+    else
+        ipt += icnt
+    end
+    if (ipt < length(fb.records))&&(ipt > 0)
+        fb.ipt = ipt
+        return true
+    else
+        return false
+    end
+end
+
+"""
+Read `data` from BDIO file.  
+
+## Arguments
+- `fb`: A BDIOstream type. It must be associated with a file in either `w` or `a` mode.
+- `data[:]`: A `Vector` of data to read.
+- `n` (optional): Integer. If present read `n` elements of `data[:]` from file
+
+## Examples
+```julia-repl
+julia> # Real 1000 floats from the first record of file `randoms.bdio`
+julia> fb = BDIO_open("randoms.bdio", "r")
+julia> BDIO_seek!(fb)
+julia> data = similar({Array, 1}, 1000)
+julia> BDIO_read(fb, data)
+```
+"""
+function BDIO_read(fb, vdata::Vector, n::Int64 = 0)
+
+    if (n>0)
+        nmax = n
+    else
+        nmax = length(vdata)
+    end
+    
+    if (nmax*sizeof(vdata[1]) > fb.records[fb.ipt].rlen)
+        error("Data in record not available")
+    end
+    
+    seek(fb.io,fb.records[fb.ipt].rpos)
+    for i = 1:nmax
+        vdata[i] = read(fb.io, typeof(vdata[1]))
+    end
+end
+
+"""
+Returns the len (in bytes) of the current record
+
+## Arguments
+- `fb`: A BDIOstream type. It must be associated with a file.
+
+## Examples
+```julia-repl
+julia> # Write length of all records
+julia> fb = BDIO_open("randoms.bdio", "r")
+julia> while BDIO_seek(fb)
+julia>     count += 1
+julia>     println("Record: ", count, " length: ", BDIO_get_len(fb), " bytes")
+julia> end
+```
+"""
+BDIO_get_len(fb::BDIOstream)       = fb.records[fb.ipt].rlen
+
+"""
+Returns the format of the current record
+
+## Arguments
+- `fb`: A BDIOstream type. It must be associated with a file.
+
+## Examples
+```julia-repl
+julia> # Print all BDIO_BIN_GENERIC records
+julia> fb = BDIO_open("randoms.bdio", "r")
+julia> while BDIO_seek(fb)
+julia>     count += 1
+julia>     if BDIO_get_fmt(fb)
+julia>         println("Record: ", count)
+julia>     end
+julia> end
+```
+"""
+BDIO_get_fmt(fb::BDIOstream)       = fb.records[fb.ipt].rfmt
+
+"""
+Returns the user provided info of each record
+
+## Arguments
+- `fb`: A BDIOstream type. It must be associated with a file.
+
+## Examples
+```julia-repl
+julia> # Write length of all records
+julia> fb = BDIO_open("randoms.bdio", "r")
+julia> while BDIO_seek(fb)
+julia>     count += 1
+julia>     println("Record: ", count, " user info: ", BDIO_get_uinfo(fb))
+julia> end
+```
+"""
+BDIO_get_uinfo(fb::BDIOstream)     = fb.records[fb.ipt].ruinfo
+
+end # module