Questions tagged [seekg]
89 questions
1
vote
2 answers
seekg, relative or absolute position?
I need to read an array from a file. The array is not ordered continuously in the file, have to jump "offset" bytes to get the next element.
What is more efficient, assuming that I read a very large file.
1) Use an incremental relative position.
2)…
Barak
- 41
- 4
1
vote
1 answer
Difficulty using file.seekg() (C++)
The following code only prints the file once:
#include
#include
using namespace std;
int main(int argc, const char *argv[])
{
ifstream infile;
infile.open("in", ios::binary);
char c;
while (infile.get(c))
…
James Jenkinson
- 1,563
- 2
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- 33
0
votes
1 answer
seekg and tellg miscompatibility
I am writing a C++ console application. After creating an Matrix with size(int) rowSize and columnSize, I wanted to write the letters in text file to matrix, but while loop never runs because reader's location is -1, and I couldn't take it to 0. Any…
Yagiz
- 1,033
- 2
- 21
- 47
0
votes
1 answer
"seekg identifier not found"
I have a program called main:
#include
#include
using namespace std;
#include"other.h"
int main()
{
//do stuff
}
and then other.h:
char* load_data(int begin_point,int num_characters)
{
seekg(begin_point);
char*…
user98188
0
votes
1 answer
seekg does not work after while(file.good()) {....}
I'm fairly perturbed that the below does not appear to work.
while(myfile.good())
{
myfile.get(holdc);
....................
}
//does not work
myfile.seekg(0);
myfile.read(buffer,5);
sentence.push_back(buffer);
cout <<…
VSB
- 232
- 1
- 4
- 13
0
votes
2 answers
tellg returning negative value after using getline and seekg
I am needing to parse through a text file and output the vowels within this textfile line by line into a separate file. This all needs to be done using one filestream at a time.
I open the input stream using fstream ios:: in & ios::binary, read in…
lostcoder
- 11
0
votes
0 answers
seekg() before each .get() call VS seekg() before for loop
I am just trying to read simple text file with ifstream. Suppose my text file looks like this (I don't know how to properly format it here, so here is how I wrote it notepad):
a\tb\nc\t\d\n
Output from reading text file using .seekg() before each…
user859v
- 1
- 1
- 1
0
votes
0 answers
Looping with seekg() is not behaving as expected
I'm getting behavior with seekg() that I don't understand. I avoid the C++ stream libraries as much as possible, so I'm sure I'm just missing something simple.
The problem happens when calling seekg() as an index into the file. I would expect it…
Rez Bot
- 13
- 1
- 2
0
votes
1 answer
seek from end of a istringstream fails
Here is a minimalist code :
#include
#include
#include
int main ()
{
std::string str = "spam" ;
std::istringstream isz( str ) ;
isz.seekg( 1,std::ios_base::beg ) ; std::cout << isz.fail() ;
…
Captain'Flam
- 479
- 4
- 12
0
votes
1 answer
seekg() seeminlgy skipping characters past intended position C++
I've been having an issue with parsing through a file and the use of seekg(). Whenever a certain character is reached in a file, I want to loop until a condition is met. The loops works fine for the first iteration but, when it loops back, the file…
Idalas
- 51
- 8
0
votes
1 answer
seekg after reading to the end of the file
I'm trying to use the code below on the ifstream twice - before I read anything from the file, and after I read to the end of it (using readline()).
m_hexFile->m_ifsteam->seekg(0, m_hexFile->m_ifsteam->ios_base::end);
test1 =…
user3007875
- 123
- 7
0
votes
0 answers
Several input streams vs one input stream with seekg
I have a large (text) file that is divided into d "chunks". The user can read the next line from either of these chunks - the order is not specified. The file is not changed in the process.
There are two obvious solutions: Maintaining d input…
mike
- 75
- 2
0
votes
0 answers
reading and writing to a file with fstream
bool remove_vowels(const std::string& file_name) {
std::fstream fs{ file_name , std::ios_base::in | std::ios_base::out };
if (!fs) { std::cout << "Error file not open"; return false; }
char in{};
while (fs >> in) {
…
user12623797
0
votes
0 answers
After writing binary file and reading a record (an object) from the binary file, enum type last attribute of the record is NULL ( default value)
I'm trying to write a C++ code that read from a text file, write all the contents into a binary file, and read a record from the binary file.To hold records, I created a Student class that one of its attribute is enum type.I read from text file…
Denisa
- 125
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- 16
0
votes
1 answer
Cant understand how to use seekg tellg to achieve the following result
As part of a larger program, my task is to read each line of an input file and store the index offset to each line. Later given all the index offsets, I want to be able to go to that position in the file directly and print the line corresponding to…
batwing
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