A file handle is an abstract indicator for accessing a file. It is retrieved after successfully opening the file using the file name. Afterwards the file handle is used instead of the file name for all file operations.
Questions tagged [filehandle]
407 questions
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fflush fails on Visual C++ 2010
I'm trying to run some code but fflush() with the error:
Invalid file descriptor. File possibly closed by a different thread
Here is the relevant part of the code:
fhandle = fopen("dbfile.bin", "rbc");
/* There is a valid dbfile.bin file -…
chustar
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How do I release a file handle with Qt QMovie?
I have written a simple image viewer. It can view the images just fine, but when it tries to shutil.move a .gif file played with QMovie it crashes. Problem is a still open filehandle. How do I close the filehandle while still playing the gif?
This…
StackHogger
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How to write text file in python3.x?
I am unable to write to a text file. My function looks like this. The file is created but after running the code the file remains empty. I am unable to figure out what the problem is.
def compare(prjCode, prjName, stCode, stName, dCode, dName,…
Karan Gupta
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Does reading a binary file linewise in python cause problems for unicode data?
I'm reading a large (10Gb) bzipped file in python3, which is utf-8-encoded JSON. I only want a few of the lines though, that start with a certain set of bytes, so to save having to decode all the lines into unicode, I'm reading the file in 'rb'…
user2667066
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Swift FileHandle seek/readData performance
Context:
I have a project where I store a lot of data in Binary files and Data files. I retrieve offsets in a Binary file, stored as UInt64, and each of these offsets give me the position of an utf-8 encoded String in another file.
I am attempting,…
Scaraux
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How do I merge specific columns from files in array or hash of multiple file handles, one line at a time?
I'll start by describing the files I am working with:
./groupA
./groupA/fileA.txt
./groupA/fileB.txt
./groupA/fileC.txt
./groupA/fileD.txt
./groupB
./groupB/fileA.txt
./groupB/fileB.txt
./groupB/fileC.txt
etc.
Here is…
Alex Reynolds
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4-Argument-Select-Question
From SELECT_TUT:
"... is used to efficiently monitor multiple file descriptors, to see if any of them is, or becomes, "ready"; that is, to see whether I/O becomes possible, or an "exceptional condition" has occurred on any of the descriptors.
…
sid_com
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iOS : Write ByteArray ( [Int8] ) to a file in swift 4
I am developing an application for iOS using swift 4.
I need to write ByteArray [Int8] to a file in applicationSupportDirectory.
And later i need to upload the file on my server to read it and do the operations.
My server is on java platform.
The…
sohaib karim
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Unclosed file handle when filtering file lines
I've noticed that following code snippet in Groovy lefts unclosed file handle in JVM. I cannot remove this file until GC runs and closes resource by invoking finalizer.
StringWriter writer = new StringWriter()
new File("file.txt").filterLine(writer)…
Michal Kordas
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2 answers
Where to close a file handle opened at the beginning of a PHP script?
I have a PHP file in which, on the top I create a file handle using fopen(). Then then file has a couple of classes, in the functions of which I write stuff to this text file. And ultimately, in the end, i.e. when I am done writing stuff to this…
Shy
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get the file name from the file handle value
let's say I have a filehandle. Is there a way for me to know the name of the file it is writing to?
I.e., you usually use:
set fh [ open "fname" "w" ]
I want a proc that would have the output:
puts [ getFHFName $fh]
>fname
Any ideas?
user1134991
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FileHandle not accepting my URLs for write access
I'd like to open a uniquely named output file for writing either plist or data, but not having any luck in getting a handle using either URL routine of init(fileURLWithPath:) or init(string:)
func NewFileHandleForWritingFile(path: String, name:…
slashlos
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Getting file handle as an argument
In bash redirection, I asked a question and got an answer as follows.
With cat < file, cat reads from its standard input; the shell opens the file and connects the file handle to cat
Now, I’m curious how this is possible. I mean, how a…
plhn
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Is there a way to open a file in a shared folder using the file id(FILE_ID_DESCRIPTOR) obtained from GetFileInformationByHandle()
Currently, i'm using the following functions to open the file using its id.
volHandle = CreateFile(pVolName, ...);
fileHandle = OpenFileById(volHandle, &id, ...)
The id(FILE_ID_DESCRIPTOR) is obtained from GetFinalPathNameByHandle().
This works for…
kuarissu
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Perl - Start reading from specific line, and only get first column of it line, until end
I have a text file that looks like the following:
Line 1
Line 2
Line 3
Line 4
Line 5
filename2.tif;Smpl/Pix & Bits/Smpl are missing.
There are 5 lines that are always the same, and on the 6th line is where I want to start reading data. Upon…
drewrockshard
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