Search Results

Search found 60836 results on 2434 pages for 'system io directory'.

Page 250/2434 | < Previous Page | 246 247 248 249 250 251 252 253 254 255 256 257  | Next Page >

• [c++] How to create a std::ofstream to a temp file?

  - by dehmann

  Okay, mkstemp is the preferred way to create a temp file in POSIX. But it opens the file and returns an int, which is a file descriptor. From that I can only create a FILE*, but not an std::ofstream, which I would prefer in C++. (Apparently, on AIX and some other systems, you can create an std::ofstream from a file descriptor, but my compiler complains when I try that.) I know I could get a temp file name with tmpnam and then open my own ofstream with it, but that's apparently unsafe due to race conditions, and results in a compiler warning (g++ v3.4. on Linux): warning: the use of `tmpnam' is dangerous, better use `mkstemp' So, is there any portable way to create an std::ofstream to a temp file?

  Read the article

• Reading a large text file to memory in C++

  - by NoneType

  Is there a way to read a large text file (~60MB) into memory at once (like a compiler flag to increase program memory limit) ? Currently, ofstream's open function throws a segmentation fault while trying to read this file. ifstream fis; fis.open("my_large_file.txt"); // Segfaults here The file just consists of rows of the form number_1<tabspace>number_2 i.e., two numbers separated by a tabspace.

  Read the article

• [C] Read line from file without knowing the line length.

  - by ryyst

  Hi, I want to read in a file line by line, without knowing the line length before. Here's what I got so far: int ch = getc(file); int length = 0; char buffer[4095]; while (ch != '\n' && ch != EOF) { ch = getc(file); buffer[length] = ch; length++; } printf("Line length: %d characters.", length); I can now figure out the line length, but only for lines that are shorter than 4095 characters. Is there a better way to do this (I already used fgets() but got told it wasn't the best way)? --Ry

  Read the article

• read text files containing binary data as a single matrix in matlab

  - by user1716595

  I have a text file which contains binary data in the following manner: 00000000000000000000000000000000001011111111111111111111111111111111111111111111111111111111110000000000000000000000000000000 00000000000000000000000000000000000000011111111111111111111111111111111111111111111111000111100000000000000000000000000000000 00000000000000000000000000000000000011111111111111111111111111111111111111111111111111111111100000000000000000000000000000000 00000000000000000000000000000000000111111111111111111111111111111111111111111111111111111111100000000000000000000000000000000 00000000000000000000000000000000000011111111111111111111111111111111111111111111111111111111100000000000000000000000000000000 00000000000000000000000000000000000000011111111111111111111111111111111111111111111111111111100000000000000000000000000000000 00000000000000000000000000000000000000011111111111111111111111111111111111111111111111000111110000000000000000000000000000000 00000000000000000000000000000000000000111111111111111111111111111111111111111111111111111111110000000000000000000000000000000 00000000000000000000000000000000000000000000111111111111111111111111111111111111110000000011100000000000000000000000000000000 00000000000000000000000000000000000000011111111111111111111111111111111111111111111111100111110000000000000000000000000000000 00000000000000000000000000000000000111111111111111111111111111111111111111111111111111110111110000000000000000000000000000000 00000000000000000000000000000000001111111111111111111111111111111111111111111111111111111111100000000000000000000000000000000 00000000000000000000000000000000000000001111111111111111111111111111111111111111111111000011100000000000000000000000000000000 00000000000000000000000000000000000000001111111111111111111111111111111111111111111111000011100000000000000000000000000000000 00000000000000000000000000000000000001111111111111111111111111111111111111111111111111111111000000000000000000000000000000000 00000000000000000000000000000000000000011111111111111111111111111111111111111111111110000011100000000000000000000000000000000 00000000000000000000000000000000000000000000011111111111111111111111111111111111100000000011100000000000000000000000000000000 00000000000000000000000000000000000000111111111111111111111111111111111111111111111111110111100000000000000000000000000000000 Plz note that each 1 or 0 is independent i.e the values are not decimal.I need to find the column wise sum of the file.There are 125 columns in all (here it is jumping onto the next line) and there are 840946 rows. I have tried textread,fscanf and a few other matlab commands but the result is that they all read each row in decimal format and create a 840946*1 array.I want to create a 840946*125 array to compute a column wise sum. Kindly help, Thanks!

  Read the article

• What influences running time of reading a bunch of images?

  - by remi

  I have a program where I read a handful of tiny images (50000 images of size 32x32). I read them using OpenCV imread function, in a program like this: std::vector<std::string> imageList; // is initialized with full path to the 50K images for(string s : imageList) { cv::Mat m = cv::imread(s); } Sometimes, it will read the images in a few seconds. Sometimes, it takes a few minutes to do so. I run this program in GDB, with a breakpoint further away than the loop for reading images so it's not because I'm stuck in a breakpoint. The same "erratic" behaviour happens when I run the program out of GDB. The same "erratic" behaviour happens with program compiled with/without optimisation The same "erratic" behaviour happens while I have or not other programs running in background The images are always at the same place in the hard drive of my machine. I run the program on a Linux Suse distrib, compiled with gcc. So I am wondering what could affect the time of reading the images that much?

  Read the article

• How to read a single character at a time from a file?

  - by kaushik

  I want to read a single character at a time from a file in python. Can anyone tell me how can I do this?

  Read the article

• std::string equivalent for data with NULL characters?

  - by known

  I'd like to read a binary file and use something like std::string that automatically resizes the buffer and such. I'm using Visual C++. What are my options?

  Read the article

• How do I read and write to a file using threads in java?

  - by WarmWaffles

  I'm writing an application where I need to read blocks in from a single file, each block is roughly 512 bytes. I am also needing to write blocks simultaneously. One of the ideas I had was BlockReader implements Runnable and BlockWriter implements Runnable and BlockManager manages both the reader and writer. The problem that I am seeing with most examples that I have found was locking problems and potential deadlock situations. Any ideas how to implement this?

  Read the article

• How to list the contents of a .zip folder in c#?

  - by vbroto

  How to list the contents of a zipped folder in C#? For example how to know how many items are contained within a zipped folder, and what is their name?

  Read the article

• Preventing threads from writing to the same file

  - by EpsilonVector

  I'm implementing an FTP-like protocol in Linux kernel 2.4 (homework), and I was under the impression that if a file is open for writing any subsequent attempt to open it by another thread should fail, until I actually tried it and discovered it goes through. How do I prevent this from happening? PS: I'm using open() to open the file.

  Read the article

• Likelihood of IOError during print vs. write

  - by jkasnicki

  I recently encountered an IOError writing to a file on NFS. There wasn't a disk space or permission issue, so I assume this was just a network hiccup. The obvious solution is to wrap the write in a try-except, but I was curious whether the implementation of print and write in Python make either of the following more or less likely to raise IOError: f_print = open('print.txt', 'w') print >>f_print, 'test_print' f_print.close() vs. f_write = open('write.txt', 'w') f_write.write('test_write\n') f_write.close() (If it matters, specifically in Python 2.4 on Linux).

  Read the article

• How does including a .csv work in an enum?

  - by Tommy

  enum ID // IDs { ID_HEADER = 0, // ID 0 = headers #include "DATA.CSV" ID_LIMIT }; I inherited some code here..... Looking at "DATA.CSV" I see all the ID's used to populate the enum in column B, along with other data. My question: How does the enum know that it is using "column B" to retrieve it's members? There must be some other logic in the application yet I don't see it. What else should I look for? Thanks.

  Read the article

• Write to a file stream returned from getResourceAsStream()

  - by Andreas Grech

  I am getting a a InputStream from getResourceAsStream(), and I managed to read from the file by passing the returned InputStream to a BufferedReader. Is there any way I can write to the file as well?

  Read the article

• File System Types in .Net

  - by Avi

  I don't get the abstractions and the terminology :-( For example, DirectoryInfo.FullName is defined as the full path of the directory or file, but it's a string! So is DirectoryInfo.Name, FileInfo.FullName, Path.GetDirectoyName and so on. This means that in .Net there is no "depth" (or "meat" - my English isn't so good) for the file system objects. There's no protection from a type system. I can't, for example, define two Path objects and ask if one of them is "above" the other - I have to manipulate the strings. I can't differentiate between a Path that identifies a directory and a path that identifies a file. I can't do anything!-( Just manipulate strings. Is this correct (or am I simply missing something). If correct, are there any alternatives?

  Read the article

• How do i force a file to be deleted? Windows server 2008

  - by acidzombie24

  On my site a user may upload a file (pic, zip, audio, video, whatever). He then may decide to replace it with a newer revision. This user may upload a file, make a post then decide to put up a new revision replacing the old (lets say its a large zip or tar.gz file). Theres a good chance people may be downloading it if he sent out an email or even im for the home user. Problem. I need to replace the file and people may be downloading and it may be some minutes before it is deleted. I dont want my code to stall until i cant delete or check every second to see if its unused (especially bad if another user can start and he takes long creating a cycle). How do i delete the file while users are downloading the file? i dont care if they stop i just care that the file can be replaced and new downloads are the new revision.

  Read the article

• Why are some programs writing on stderr instead of stdout their output?

  - by Zagorax

  I've recently added to my .bashrc file an ssh-add command. I found that ssh-add $HOME/.ssh/id_rsa_github > /dev/null results on a message "identity added and something else" every time I open a shell. While ssh-add $HOME/.ssh/id_rsa_github > /dev/null 2>&1 did the trick and my shell is now 'clean'. Reading on internet, I found that other command do it, (for example time). Could you please explain why it's done?

  Read the article

• Is there a standard place to store Spring library jar files?

  - by richj

  I've downloaded Spring 3.0.2 with dependencies and found that it contains 405 jar files. I usually keep third party libraries in a "lib" subdirectory, but there are so many Spring jars that it seems sensible to keep them separately so that they don't swamp the other libraries and to simplify version upgrades. I suspect that I want to keep the full set of libraries in Subversion, but only deploy the subset that is actually used. Do Spring users have a standard way to deal with this problem?

  Read the article

• How to authenticate a user/application combination in Oracle?

  - by Martin R-L

  I'd like to authenticate the user/application combination, not only the user. The scenario is that we've built an app that guides the user to safe updates of some data. If the same user installs PL/SQL Dev, Toad, or any other Oracle management tool, she can edit the data in ways that the app prohibits.

  Read the article

• C read part of file into cache

  - by Pete Jodo

  I have to do a program (for Linux) where there's an extremely large index file and I have to search and interpret the data from the file. Now the catch is, I'm only allowed to have x-bytes of the file cached at any time (determined by argument) so I have to remove certain data from the cache if it's not what I'm looking for. If my understanding is correct, fopen (r) doesn't put anything in the cache, only when I call getc or fread(specifying size) does it get cached. So my question is, lets say I use fread and read 100 bytes but after checking it, only 20 of the 100 bytes contains the data I need; how would I remove the useless 80 bytes from cache (or overwrite it) in order to read more from the file.

  Read the article

• How to modify this c++ code so it doesn't overwrite the whole file

  - by Phenom

  ofstream f("test",app); f.seekp(5,ios::beg); f << "hello world"; f.close(); What I'm trying to do here is open a file that already has data in it, and then put "hello world" somewhere in the middle of the file. However, when I run my code, it overwrites the whole file. How can this code be fixed?

  Read the article

• Python to extract data from a file

  - by user297003

  Hi, I am new to python. I am trying to extract the text between that has specific text file: ---- data1 data1 data1 extractme ---- data2 data2 data2 ---- data3 data3 extractme ---- and then dump it to text file so that ---- data1 data1 data1 extractme --- data3 data3 extractme --- Thanks for the help.

  Read the article

• lib to read a DVD FS (data disc)

  - by acidzombie24

  I am thinking i might want to port a lib to read a DVD filesystem. I am not talking about movies but datadisc. Theres existing code for me to do raw reads from the disc. I need code that request this data and allow me to browse files on the disc. What lib can i use for this? -edit- NOTE: I am using an OSless hardware. Ppl seem to miss that but Alnitak caught it and gave me a great answer :)

  Read the article

• .NET Best Way to move many files to and from various directories??

  - by Dan

  I've created a program that moves files to and from various directories. An issue I've come across is when you're trying to move a file and some other program is still using it. And you get an error. Leaving it there isn't an option, so I can only think of having to keep trying to move it over and over again. This though slows the entire program down, so I create a new thread and let it deal with the problem file and move on to the next. The bigger problem is when you have too many of these problem files and the program now has so many threads trying to move these files, that it just crashes with some kernel.dll error. Here's a sample of the code I use to move the files: Public Sub MoveIt() Try File.Move(_FileName, _CopyToFileName) Catch ex As Exception Threading.Thread.Sleep(5000) MoveIt() End Try End Sub As you can see.. I try to move the file, and if it errors, I wait and move it again.. over and over again.. I've tried using FileInfo as well, but that crashes WAY sooner than just using the File object. So has anyone found a fool proof way of moving files without it ever erroring? Note: it takes a lot of files to make it crash. It'll be fine on the weekend, but by the end of the day on monday, it's done.

  Read the article

• SharePoint Returning a 401.1 for a Specific User/Computer

  - by Joe Gennari

  We have a SharePoint Services 3.0 site set up supporting about 300 users right now. This report is isolated and has never been duplicated. We have one AD user who cannot log into the SharePoint site with his account from his machine and is subsequently returned a 401.1 error. If any other user tries to log on with their account from his machine, it works okay. If he moves to another machine and logs on, it works okay. The only solution to this point has been to install FireFox on the machine. When he authenticates with FF, everything is okay. Remedies tried so far: Cleared cookies/cache Turned off/on Integrated Windows Authentication in IE Downgraded IE 8 to IE 6 Removed site from Intranet Sites zone Renamed the machine Disjoined/Rejoined Domain

  Read the article

• How to pass a file (read from Java) most effectively to a native method?

  - by soc

  Hi, I have approx. 30000 files (1MB each) which I want to put into a native method, which requires just an byte array and the size of it as arguments. I looked through some examples and benchmarks (like http://nadeausoftware.com/articles/2008/02/java_tip_how_read_files_quickly) but all of them do some other fancy things. Basically I don't care about the contents of the file, I don't want to access something in that file or the byte array or do anything else with it. I just want to put a file into a native method which accepts an byte array as fast as possible. At the moment I'm using RandomAccessFile, but that's horribly slow (10MB/s). Is there anything like byte[] readTheWholeFile(File file){ ... } which I could put into native void fancyCMethod(readTheWholeFile(myFile), myFile.length()) What would you suggest?

  Read the article

< Previous Page | 246 247 248 249 250 251 252 253 254 255 256 257  | Next Page >