For 2023 - we are now fully retired from IT training.
We have made many, many friends over 25 years of teaching about Python, Tcl, Perl, PHP, Lua, Java, C and C++ - and MySQL, Linux and Solaris/SunOS too. Our training notes are now very much out of date, but due to upward compatability most of our examples remain operational and even relevant ad you are welcome to make us if them "as seen" and at your own risk.
Lisa and I (Graham) now live in what was our training centre in Melksham - happy to meet with former delegates here - but do check ahead before coming round. We are far from inactive - rather, enjoying the times that we are retired but still healthy enough in mind and body to be active!
I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
Strings in C - strncmp strncpy and friends
Strings in C are pointers to arrays of characters, null (\0) terminated. Which means that if you compare them with the == operator, you're going to be comparing addresses, and not whether the strings contain the same text. And even if you put a "*" in front of the variable you're comparing, all you'll do is compare the first character.
Solution is to use standard functions such as strcmp and strcpy - string compare and string copy. Both of these are regarded as dangerous as they can run off the end of stings that aren't properly null terminated, so you also have strncmp and strncpy which are better regarded, and have an extra parameter which is the maximum number of characters to compare / copy.
Similarly, fgets to read in a string (use stdin for the keyboard) with a maximum length is much safer that gets which can easiiy be overrun by a too-long input!
Be careful too of strcmp and strncmp - they return 0 if the strings are equal - that's a false value and the opposite of what you would expect ... and they return +1 if the first value is logically (ascibetically) before the second, and -1 if it's after. Once you realise this is done to help you sort / order strings, it's logical - but it catches newcomers out all the time!
from yesterday's C course - see [here]
. (written 2015-10-27)
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articlesC206 - C and C based languages - Character Strings 
Handling Binary data in Tcl (with a note on C) - (2007-09-09) 
String functions in C - (2010-06-30) 
Learning about Regular Expressions in C through examples - (2010-06-30) 
When is a program complete? - (2011-01-06) 
Setting up arrays in C - fixed size at compile time, or dynamic - (2011-01-24) 
Strings in C - (2011-01-25) 
Chars, char arrays and strings in C. Some early cautions and pitfalls. - (2012-01-26) 
Splitting a record into individual data values in C - (2012-05-04) 
Simple C structs - building up to full, dynamic example - (2014-12-03) 
String handling in C - new examples of extracting integers from a string - (2016-01-27)
Some other Articles
Variables, Pointers and References - C and C++When do I use the this keyword in C++?Well House Consultants - Python courses / what's special.Function prototype - what they are and why you should use them - C and C++Strings in C - strncmp strncpy and friendsPreprocessor directives in C and C++ - what they meanPassing information into functions in C - by name, by valueRUby - loading, using, changing, storing JSON format dataScenario outlines - tables of values to test - in Gherkin / CucumberTesting your new class - first steps with cucumber
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