Blog

Can two Ifstream objects open the same exact file to read from it?

Can two Ifstream objects open the same exact file to read from it?

Having two openings of the same file might cause an inconsistent view between the files, depending on the underlying OS. For a third option, pass a reference or raw pointer into the other thread. So long as the semantics are that one thread “owns” the istream, the raw pointer or reference are fine.

How read a variable from a file in C++?

In order for your program to read from the file, you must:

  1. include the fstream header file with using std::ifstream;
  2. declare a variable of type ifstream.
  3. open the file.
  4. check for an open file error.
  5. read from the file.
  6. after each read, check for end-of-file using the eof() member function.
READ ALSO:   Will biotin help my eyebrows grow back?

Why should we not open the same file from two different programs at the same time?

The danger when multiple users are using the same files is that if two people edit a file at the same time, the file is guaranteed to be corrupted. Be sure that you’re working on the most current version of a file! …

How do I read a text file in Word by Python?

Approach:

  1. Open a file in read mode which contains a string.
  2. Use for loop to read each line from the text file.
  3. Again use for loop to read each word from the line splitted by ‘ ‘.
  4. Display each word from each line in the text file.

How can fscanf read string?

The fscanf() function reads data from the current position of the specified stream into the locations that are given by the entries in argument-list , if any. Each entry in argument-list must be a pointer to a variable with a type that corresponds to a type specifier in format-string .

READ ALSO:   How do you change a washer on a old fashioned tap?

Does fscanf read new line?

3 Answers. This will eat all whitespace characters, including new-lines. Quotation from cplusplus.com: Whitespace character: the function will read and ignore any whitespace characters encountered before the next non-whitespace character (whitespace characters include spaces, newline and tab characters — see isspace).

Why is the last line of the eofbit set twice?

is carried out, the eofbit gets set. The last line is printed twice, because all the read operations during the last loop iteration fail and the variables still have the values from the previous loop iteration. Edit: To prevent that you could check whether the read operations were successful, e.g. by using inFile.good () in the loop:

Is it possible to read only part of a struct?

It is possible to read in only a partial struct which is probably not what you want. It is also possible that your loop will execute an extra time. You should instead check to see that the value that fscanf returns is >= sizeof(your_struct). That way you know that you have read in an entire struct.

READ ALSO:   Is RMON a SNMP?

What is the difference between imread and a = imread ( filename)?

A = imread (filename) reads the image from the file specified by filename, inferring the format of the file from its contents. If filename is a multi-image file, then imread reads the first image in the file. A = imread (filename,fmt) additionally specifies the format of the file with the standard file extension indicated by fmt.

How does the readmatrix function work?

The readmatrix function performs automatic detection of import parameters for your file. .xls, .xlsb, .xlsm , .xlsx, .xltm, .xltx, or .ods for spreadsheet files For files containing mixed numeric and text data, readmatrix imports the data as a numeric array by default. A = readmatrix (filename,opts) additionally uses the import options opts.