How to provide buffer size dynamically.

[Man4ish]

Hi,

Normally when we read a file we need to provide buffer size. How it can be provided dynamically to save the space and time.


Regards

[Banfa]

That problem description is too vague for us to answer clearly. That is people may answer but because your description is so vague there is a high probability that they will misinterpret you and give you the answer to a different question to the one you are trying to ask.

It is common for small to medium size files to get the size of the file first and allocate a buffer large enough to hold the entire file before reading it in.

Reading a line at a time into a string in C++ you don't need to know the size of the line the library sizes the string to the required size.

[Man4ish]

Thanks for our answer which is appropriate but using string class will be slower. Is there any way to allocate the buffer size dynamically?

[Banfa]

Use new (or malloc if it is C)

[weaknessforcats]

Do a seek to the end of the file followed by a tell. That will get you the number of bytes in the file. Allocate that amount.