The following code will give you a hex dump of arbitrary memory from within your code. #include <stdio.h> // Usage: // hexDump(desc, addr, len, perLine); // desc: if non-NULL, printed as a description before hex dump. // addr: the address to start dumping from. // len: the number of bytes to dump. // perLine: number … Read more
This really depends on the nature of the binary data, and the constraints that “text” places on your output. First off, if your binary data is not compressed, try compressing before encoding. We can then assume that the distribution of 1/0 or individual bytes is more or less random. Now: why do you need text? … Read more
Here is the binary equivalent of COPY FROM for Python 3: from io import BytesIO from struct import pack import psycopg2 # Two rows of data; “id” is not in the upstream data source # Columns: node, ts, val1, val2 data = [(23253, 342, -15.336734, 2494627.949375), (23256, 348, 43.23524, 2494827.949375)] conn = psycopg2.connect(“dbname=mydb user=postgres”) curs … Read more
For storing binary data like images you can use GridFS or implement your own realization; Download the driver and look at src/test/com/mongodb/gridfs/GridFSTest.java 😉 Edit: you are lucky today! I made complete code for you;) Enjoy! package mongodb.testing.java; import com.mongodb.*; import com.mongodb.gridfs.*; import java.io.*; public class Main { public static byte[] LoadImage(String filePath) throws Exception { … Read more
If file sizes could be specified accurate to the bit, for any file size N, there would be precisely 2^(N+1)-1 possible files of N bits or smaller. In order for a file of size X to be mapped to some smaller size Y, some file of size Y or smaller must be mapped to a … Read more
Will simply sending base64 encoded data work? There is no need to use base 64 encoding – this will simply increase the number of bytes you must transfer. Mobile operators normally limit mangling of responses to content types that they understand – i.e. images, stylesheets, etc. How are the HTTP sessions handled? HTTP sessions are … Read more
No, it is not always reliable when you have binary blobs. In that case you MUST use the “–hex-blob” flag to get correct results. Caveat from comment below: If you combine the –hex-blob with the -T flag (file per table) then the hex-blob flag will be ignored, silently I have a case where these calls … Read more
The advantage of storing data in the DB is taking advantage of DB security mechanisms and reducing maintanence cost (backups, …). The disadvantage of it is increasing DB load and consuming connections (which might be expensive for per-connection licensed database servers). If you are using SQL Server 2008, FILESTREAM might be a nice alternative. By … Read more
vector of char is nice because the memory is contiguious. Therefore you can use it with a lot of C API’s such as berkley sockets or file APIs. You can do the following, for example: std::vector<char> vect; … send(sock, &vect[0], vect.size()); and it will work fine. You can essentially treat it just like any other … Read more
Is there any solution like building a pdf file on file system in order to let the user download it? Try setting responseType of XMLHttpRequest to blob , substituting download attribute at a element for window.open to allow download of response from XMLHttpRequest as .pdf file var request = new XMLHttpRequest(); request.open(“GET”, “/path/to/pdf”, true); request.responseType … Read more