Getline from a text file

If you run the same code on macOS the line buffer is resized to bytes. This is due to the different ways in which getline is implemented on different Unix like systems. As mentioned before, getline is not present in the C standard library. It could be an interesting exercise to implement a portable version of this function. The idea here is not to implement the most performant version of getline , but rather to implement a simple replacement for non POSIX systems. Obviously, if you are on a POSIX system, you should use the version provided by the operating system, which was tested by countless users and tuned for optimal performance.

This is how we can use the above function, for simplicity I kept the code and the function definition in the same file:. Kernighan, D. C Programming - read a file line by line with fgets and getline, implement a portable getline version Posted on April 3, by Paul In this article, I will show you how to read a text file line by line in C using the standard C function fgets and the POSIX getline function. Vestibulum porttitor aliquam luctus. Cras egestas nunc vitae eros vehicula hendrerit.

Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow.

Learn more. Asked 11 years, 7 months ago. Active 5 years, 2 months ago. Viewed k times. Improve this question. Eternal Learner Eternal Learner 3, 12 12 gold badges 45 45 silver badges 76 76 bronze badges. DannyBeckett Yes I noticed. I don't think that's relevant to my point, as this one unlike the other asks about C, which makes it qualitatively different. Add a comment. Active Oldest Votes. Improve this answer. Jacob Jacob 3, 2 2 gold badges 17 17 silver badges 25 25 bronze badges.

How would we do the same in C? Updated my post with how I recall doing it, I hope it is correct as I put it, otherwise I'll correct the post once people point out what I did wrong. Thanks, I was wondering if there was a better way than using a buffer of fixed length.

I'm having a bit of a problem with extracting data from a simple. The txt file is very simple: a column of numbers. I use a vector to store them with the following code:. So you should use std::stod to convert the line read by getline into a double. That is - you can use either but not both. What is worse that is oddly converted to double:. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?

Collectives on Stack Overflow. Learn more. Getline to read data from txt file Ask Question. Asked 3 years, 7 months ago. Active 3 years, 7 months ago. Viewed 1k times. I tried several other ways to extract this data but it was unsuccessful.

Thank you for your help! Improve this question. Einsiedler Einsiedler 33 8 8 bronze badges. I have updated the code with the variables declaration. Add a comment. Active Oldest Votes. Improve this answer. Maxim Egorushkin Maxim Egorushkin k 14 14 gold badges silver badges bronze badges.