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While writing into a file , Where intermediate data stored in between fopen() and fclose()?

c,fopen,file-handling,fclose

When you open a file with fopen, the output you write is buffered, meaning it's not actually send to the lower layers until the buffer is either full or you explicitly flush it with fflush. Also note that the layers under fopen/fprintf/fclose, all the way down to the actual hardware,...

How to remove a particular word from a text that satisfies a condition?

java,file-handling

Regular expressions may work for you. Something like Pattern p = Pattern.compile("([a-zA-Z])*([a-zA-Z])\\2([a-zA-Z])*"); Matcher m = p.matcher("zoo"); System.out.println(m.matches()); Just add a loop to try every word in file and if m.matches() == true - delete it. By the way, this won't work if you tYpE lIkE ThIs...

PHP Search Not Matching Line in File

javascript,php,file-handling,strpos,comparison-operators

There are a lot of mistakes in your code. Some of them are already noted. You should use "===" and it's good to trip line-ending symbols. But main problem as I see is that you check in for loop, but exiting after very first string that does not contain correct...

How to avoid doing processes on a given directory name in vb.net

vb.net,linq,loops,file-io,file-handling

I would create a Dictionary or Collection object that you can load from a config file and just check before delete that the file or directory is not in the collection. You are effectively making a white-list of what items should never be removed, which can be modified at any...

How do I find out if one Python function is an alias for another one?

python,file,alias,file-handling

In Python 3, the open() function is indeed the same object: >>> sys.version '3.4.2 (default, Nov 29 2014, 18:28:46) \n[GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.54)]' >>> id(open) 4467734600 >>> id(io.open) 4467734600 >>> io.open is open True This is not the case in Python 2 however. The io module is...

C# Scoreboard .txt scoreboard making for a tetris game

c#,linq,sorting,io,file-handling

you can use linq to achieve what you want by using the code below var scores = File.ReadAllLines("C:\\asd.txt") .Select(x => x.Split(":".ToCharArray())) // split name and score .Select(x => new { Name = x[0], Score = int.Parse(x[1]) }) // create an object contains name and score for each line .OrderByDescending(x =>...

Save Arraylist to file android

android,arraylist,file-handling

You're unable to see the file because you used openFileOutput() which creates the file on device's internal storage directory. Files created here are private to your application and aren't even visible to the the user. These files are automatically removed if the user uninstalls the application. To write a file...

How to check whether ifstream is end of file in C++

c++,ifstream,file-handling,line-endings,seekg

while( file_input.peek() != EOF ) { // code } Basically peek() will read the next char without extracting it. So you can simply compare it to EOF....

Is it necessary to close a file number of time it is opened in program?

c,file-handling

The open function is the underlying primitive for the fopen and freopen functions, that create streams. int open (const char *filename, int flags[, mode_t mode]) which creates and returns a new file descriptor for the file named by filename. Initially, the file position indicator for the file is at the...

How to reset $.?

perl,file-handling

Using local with $. does something else than you think: Localizing $. will not localize the filehandle's line count. Instead, it will localize perl's notion of which filehandle $. is currently aliased to. $. is not read-only, it can be assigned to normally. 1 while <$fh>; my $i = $.;...

c file handling : unable to write after 25 y?

c,file-handling

There are two reasons for failure. If your system opens files in text mode by default, it will respond to control characters. So you must open the files in binary mode: p = fopen("three", "wb"); ... q = fopen("three", "rb"); The second failure is the use of the useless feof()....

How to make excel backup checker script get file with newest date

vba,excel-vba,file-handling

I have found a way around it using the Dir() function: 'auto check if backup exists - on click Dim i i = 1 file = Dir(path) Do While file <> "" myBool = False isnew = False backup = Right(backup, 6) If InStr(file, backup) > 0 Then myBool =...

Seek function not working in perl

perl,file-handling

You cannot seek on a pipe. Either use a temporary file or store the data in memory. Your choice as to the best solution...

Load a large text file into a string

c#,string,file-handling

Both of your attempts so far are treating the file as if it were in UTF-8. In the best case, that's going to take twice as much memory - and it's very likely to be invalid data (as UTF-8), basically. You should try specifying the encoding: var text = File.ReadAllText(path,...

Reading files into program

c++,input,output,file-handling

#include <iostream> #include <string> #include <fstream> using namespace std; int main() { ifstream inFile ("coded.txt"); //explicitly input using ifstream rather than fstream ofstream outFile ("plain2.txt"); //explicitly output using ofstream rather than fstream string str = ""; char ch; while (inFile.get(ch)) { if (ch!='\n' && ch!=' ') { //do your manipulation...

Search file for match, if not available go to next file

python,linux,search,file-handling

import os #import re -- This module can be used for more advanced processings path = '/home/anmol/Desktop/test/testing/'#path of sample files files = [fiile for fiile in os.listdir(path) if '~' not in fiile] #this generates a list with the non-hidden files, hence using '~' #os.listdir() returns a list of all the...

How to call a system file selection dialog using perl on windows?

perl,file-handling,filehandle,filehandler,fileopendialog

It's not easy, first you have to build the data structure needed by the OpenFileDialog api, interact with the system at a low level, track file handles, then get and parse the resulting structure. There are some horrible hacks where you save a windows script, and run it from perl...

read data from text file and filter content

java,file-handling

You can change your part from: while (partscan.hasNextLine()){ String mystr=partscan.nextLine(); System.out.println(mystr); } partscan.close(); To int lineNo = 0; List<String> theOnesICareAbout = new LinkedList<String>(); while (partscan.hasNextLine()){ String line=partscan.nextLine(); if (isOneOfTheImportantLines(lineNo)) { theOnesICareAbout.add(line); } } partscan.close(); Somewhere you will need a function that tells you if a given line number is one...

Python: Too many open files error

python,file,runtime-error,file-handling

You have a typo for i in megadatalist: i.close Should read for i in megadatalist: i.close() ...

Compare consecutive columns of a file and return the number of non-matching elements

python,file-handling

A Pure native python library way of solving this - let us know how it compares with bash 828 x 828 should be a walk in the park. Element Column counts: I purposely wrote this with a step in flipping of the sequences, for simplicity and illustrative purposes - you...

File Handling Error in C

c,file-handling

When you enter a number for scanf("%d",&a);, you type in a number and press the Enter key. The scanf consumes the number and leaves the newline character ('\n') in the standard input stream (stdin). When the execution of the program reaches gets(name);, gets sees the newline character and consumes it,...

counting the number of times a character appears in a file in a case insensitive manner using C language

c,file-handling,case-insensitive

I found a few errors in your code, and made a few small tweaks. The errors are - not eating the "whitespace" before the character input, using fgets() instead of fgetc(), using escape characters before the ' symbols in the output text. #include <stdio.h> #include <ctype.h> #include <stdlib.h> int main(void)...

Map filled with file names and set as request attribute by servlet appears empty in JSP

jsp,servlets,hashmap,file-handling

The File constructor needs a real path to access the local directory. So you should not access it using localhost:8080, instead you should access the directory using the real path like below String path="/home/test/apache/webapp/projectname/YouBlogger/Posts/" If you don't want to hard code the path you can use the request.getSession().getServletContext().getRealPath("/") to get...

java : File.getAbsoluteFile().exists() v/s File.exists()

java,file,file-handling

First of all read Oracle docks on exists. And getAbsoluteFile. Answer yourself what does getAbsoluteFile do? Then answer yourself do you need to get the absolute form of of your folder abstract pathname? Does it help you in anything? If not, use simpliest easy to write easy to read method...

Using a bash script to apply another script to every file in a directory like a matrix

bash,shell,matrix,scripting,file-handling

script_v1.sh: #!/bin/bash compare="/path/to/my/compare_tool" for i in {1..5}; do for j in $(seq $((i+1)) 5); do echo "Comparing $i and $j" compare filename_V000$i.txt filename_V000$j.txt > result_$i_$j.txt done done result_v1: $ > bash script_v1.sh Comparing 1 and 2 Comparing 1 and 3 Comparing 1 and 4 Comparing 1 and 5 Comparing 2...

separate a particular chunk of line through file handling [duplicate]

c#,file-handling

You can do it like this... var str = @"col1 col2 col3 21312 51245 1235 21311 12 6235"; string[] rows = str.Split('\n') .Select(r => r.Split(' ')[2]) .Skip(1) .ToArray(); ...

how to read a csv file line by line having line break and coma in fields

java,file-handling

You can read the entire file into a String variable and then use String.replaceAll() to replace the characters as you want:- File file = new File("abc.csv"); FileInputStream fis = null; fis = new FileInputStream(file); byte[] data = new byte[(int) file.length()]; fis.read(data); fis.close(); String str = new String(data, "UTF-8"); And then...

Error in Downloading large files from Server using Java

java,file,file-handling

You create a buffer with the size ofthe file you want to transfer. With big files you will get just what happened: an OutOfMemoryError, since there is not enough space on your heap for that much data. The easiest fix is to choose a smaller buffer size, like 64k. That...

file contents being overwritten

python,file-handling

You have to open the file in append mode: fileobject = open('completed.txt', 'a') Python Docs for opening file "It is good practice to use the with keyword when dealing with file objects. This has the advantage that the file is properly closed after its suite finishes, even if an exception...

VBA 7.0 in Excel, Line Input appears to add extra quotes around the line

excel,vba,excel-vba,file-handling

It's actually the Write statement that puts quotes round the strings. You should use Print instead if you don't want that.

How to create sub string in a line read from text file separated by comma

javascript,ajax,regex,file-handling

Use str.split() https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/split So first we need to split on the newline \n character to get all of the lines. Then for each line, we split on the comma , character to get each of the three substrings, as you say. Here is a verbose but simple way to do...

PHP write contents to file with user submitted data [duplicate]

php,file-handling

You need to access the variable $name while writing the name to the file. The way you are doing it now does not add the value of the variable in the string. To do so you can change : $data= 'My fname is $name and My lname is $lname'; to...

What is ios::in|ios::out?

c++,file-handling

ios::in allows input (read operations) from a stream. ios::out allows output (write operations) to a stream. | (bitwise OR operator) is used to combine the two ios flags, meaning that passing ios::in | ios::out to the constructor of std::fstream enables both input and output for the stream. Important things...

write file with define constant having error to not put his value

php,file-handling

Well, if I get it right, you have a dynamic string from DB, which somewhere contents this: '{{URL}}'. So just do simple replace like this: define("URL","http://example.com/mail.php"); $string = str_replace('{{URL}}', '{{' . URL . '}}', $string); This replaces URL text using URL value of that constant...

File handling in Python - PermissionError: [WinError 32] The process cannot access the file because it is being used by another process

python,python-3.x,file-handling

Your process is the one that has the file open (via im still existing). You need to close it first before deleting it. I don't know if PIL supports with contexts, but if it did: import os from PIL import Image while True: img_dir = r"C:\Users\Harold\Google Drive\wallpapers" for filename in...

Unable to upload data from excel to mysql using PHP

php,mysql,database,file-handling

Actually you have more than one iteration that leads to multiple sheets in same array. foreach ($objPHPExcel->getWorksheetIterator() as $worksheet) { }. So, if your excel contains more than one sheet and the next sheet have no data means blank then it count it as first and insert it to you...

When does the value of file descriptor become β€œ-1”?

c++,linux,valgrind,file-handling

If multiple threads are using the same FILE* then there are a number of problems you could be hitting if there isn't a lock around all calls to fopen, fclose and fwrite. While you are re-opening the file there may be another thread attempting to write to it. fwrite also...

Python context for file or None

python,file-handling,with-statement

You could create a "no-op" context manager: import subprocess import contextlib @contextlib.contextmanager def noop(): yield None logging = False file_path = '/tmp/out' with open(file_path, 'wb') if logging else noop() as shell_stdout: subprocess.call(['ls'], stdout=shell_stdout) When logging is True, the conditional expression returns a file object. When logging is False, it returns...

Why should we use cin.get(ch) after taking input using cin.getline() or cin?

c++,file-handling

This is because you are mixing formatted input such as cin >> something; and unformatted input such as cin.get(...). The formatted input skis all whitespace before reading data, and stops at the first whitespace after the input. [If you are reading digits, it will also stop on data that is...

should I close a file in PHP's __destruct() method?

php,destructor,file-handling,fclose

I preffer to close the file when no more writing is need or in an exception: try { //write file //close file after all reading operations has been done } catch (Exception $e) { fclose($this->handler); } This is good as an emergency or an uncatched problem, because PHP will close...

File handling in getline function

c++,getline,file-handling

That's my proposal. Hope that helps. Basically what it does, it creates three containers (see std::vector from STL). They can have infinite size (you don't have to declare it afront). The create three auxilliary variables which you then use to read from stream. The condition in while loop checks if...

Unexpected traceback on text file in Python

python,file-handling,traceback

The problem is probably when you try to write to the file, in this line: file2.write(forename,surname,score,"\n") The write method receives only one argument. Build a string as pass it as argument. For example: line_to_be_written = str(forename) + " " + str(surname) + " : " + str(score) + "\n" file2.write(line_to_be_written)...

Tring to read a text file with emoji and print it

c,text,unicode,file-handling,emoji

In Unicode encoding, emoji must take more than one bytes. Hence printing byte by byte will not help in this case. If you redirect the output to a file, you may get almost same as your file. You may try to print the string by changing locale(on Linux) or you...

Printing An External File's Contents

java,external,file-handling,file-read

Your scanner is trying to reread the file but it is at the bottom so there are no more lines to read. You have two options: Option 1 Create a new Scanner object for the same file (to start at the beginning again) and then call your while loop on...

Using Gawk and Printf in a Bash script

bash,scripting,printf,file-handling,gawk

Ignoring the issue of the outer loop and focusing on the awk part of the question, you can use sprintf to produce your filename: gawk -v RS="START_of_LINE_to_SEPARATE" 'NF{ file = sprintf("new_file_%04d.txt", ++n) print RS$0 > file }' "$i" The format specifier %04d means that the number is a digit, padded...

Closing a file when looping creates that file

python,file-handling

To me, the most straightforward way to avoid relying on the presence of the dummy file is to just catch that exception on the first time through the loop when you try to call close: if re.search('^>[a-zA-Z][a-zA-Z][a-zA-Z][a-zA-Z]', line): try: seqFile.close() except NameError: # Assuming you haven't set seqFile else where...

How do we get text from a file (word-by-word) into a 2D array in PHP?

php,arrays,parsing,file-handling

This should work for you: Just read your file into an array with file() and explode() each line by a space with array_map(). $lines = array_map(function($v){ return explode(" ", $v); }, file("yourTextFile.txt", FILE_IGNORE_NEW_LINES |FILE_SKIP_EMPTY_LINES)); ...

perl β€œor” to go through a list

perl,file-handling

"Is there an elegant way to do this?" The warning is because of multiple declarations of $fh, as has already been explained, but I would prefer to see the file selected separately, because There may be more than one file with the desired ID If the file is in dir1...

Write output of android shell command to a file

android,android-manifest,file-handling,systrace

I solved it by reading data from inputstream and writing it to a file try { Process p = Runtime.getRuntime().exec("atrace -t 5 gfx"); p.waitFor(); BufferedReader reader = new BufferedReader(new InputStreamReader(p.getInputStream())); String line = reader.readLine(); File myFile = new File("/storage/sdcard0/trac.txt"); FileOutputStream f = null; try { f = new FileOutputStream(myFile); }...

fstat() return 0, with file size 0 and errno 11

c,linux,file-handling,fstat

Netdev->queue_fd[class_id] is a file descriptor of Regular file or Any sys/fs entry or Char/Block/Network device file? if it is not a regular file then its size will not be updated after write command. check file tyeps by S_ISREG()...

Cant Find File Error PHP

php,mysql,csv,file-handling

it would be so much better if have posted an image related to your error!And as php it self has expired the mysql functions it's better to use either PDO or mysqli! i have corrected some part of the codes! please check and let me know if it has helped...

Remove trailing white-spaces from each line in a file

ruby-on-rails,ruby,file-handling

Here is the one way to modify the file content in place. # a.rb File.open "#{__dir__}/out1.txt", 'r+' do |io| r_pos = w_pos = 0 while (io.seek(r_pos, IO::SEEK_SET); io.gets) r_pos = io.tell io.seek(w_pos, IO::SEEK_SET) # line read in by IO#gets will be returned and also assigned to $_. io.puts $_.rstrip w_pos...

PHP - file handle instead of path

php,phpmailer,file-handling,filehandle

You can use the addStringAttachment() method: $mail->addStringAttachment($fileContent,$fileNameToDisplay,$encoding,$type). ...

File Handling and making directories to match in bash

bash,shell,sorting,matching,file-handling

#!/bin/bash # If there are no files match File_*.*.txt # replace File_*.*.txt by empty string shopt -s nullglob for i in File_*.*.txt; do echo "processing file $i" IFS="_." read foo num1 num2 foo <<< "$i" printf -v dir1 "Dir_%03d" "$num1" printf -v dir2 "Dir_%03d" "$num2" mkdir -pv "$dir1" "$dir2" cp...

Linked List, Stuck on file management

c,linked-list,file-handling

typedef struct Quanta { char* name; int Value; int Value1; /* To hold the second integer from line 4 onwards */ struct Quanta *next; } Quanta; Use fgets() to read till end of file and after reading each line use sscanf() to fetch the required data. I have made...

Read lines starting with numbers

python,list,readfile,file-handling

import re with open("filename") as f: for line in f: if re.match(r"^\d+.*$",line): print line ...

Why does tellp() return 0 for ios::app but not for ios::ate?

c++,file-handling

From std::ios::openmode (Section 27.5.3.1.4 of C++11) std::ios::app means to seek to the end of stream before each write. So stream may be not be at end before any write operation. No matter where the pointer is (0 or somewhere else) writing is always done at end. (Implicit seek to end...