Read a line of input faster than fgets?

c optimization file-io stdin fgets
dreamlax picture dreamlax · Apr 9, 2009 · Viewed 11.8k times · Source

I'm writing a program where performance is quite important, but not critical. Currently I am reading in text from a FILE* line by line and I use fgets to obtain each line. After using some performance tools, I've found that 20% to 30% of the time my application is running, it is inside fgets.

Are there faster ways to get a line of text? My application is single-threaded with no intentions to use multiple threads. Input could be from stdin or from a file. Thanks in advance.

Answer

anon picture anon · Apr 9, 2009

You don't say which platform you are on, but if it is UNIX-like, then you may want to try the read() system call, which does not perform the extra layer of buffering that fgets() et al do. This may speed things up slightly, on the other hand it may well slow things down - the only way to find out is to try it and see.

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