A String is a NUL terminated array of chars. Remember to allow space in the string for the NUL, and for any new line character you may have too, if you dimension it manually. And remember to add a NUL back on to the end if you extend a string by adding individual characters to it.

There are lots of standard C function for handling strings - here's a categorised list of the more basic ones:

* Searching

index find next occurence
rindex find previous occurrence of
strchr find character in a string (first occurrence)
strrchr find character in a string (last occurrence)
strpbrk find one string in another and return a pointer
strstr locate one string in another

* Comparing

strcasecmp string compare ignore case
strcmp string compare
strncmp string compare - first "n" characters
strncasecmp compare first "n" characters of 2 strings, ignoring case

* Copying

stpcpy string copy (return a pointer)
strcat join strings (concatenate)
strcpy copy string
strncpy copy first "n" characters of a string
strncat join up to "n" character of one string to another

* Scanning

strcspn how many characters in a string are not within a specified set?
strspn how many characters in a string are within a specified set?
strlen how long is a string?
strsep find a separator and return a pointer beyond it
strtok string tokeniser (you should now use strsep)

* Regular expressions - regex.h

regcomp compile a regular expression then ...
regexec ... match a regular expression and ...
regfree ... free up any internal memory used.
regerror handle regular expression error messages

Odd characters in the function name? Remember ...
c - compliment (not)
p - pointer
n - number / count
r - reverse (from end)
(written 2010-06-30)

 C206 - C and C based languages - Character Strings
  [1338] Handling Binary data in Tcl (with a note on C) - (2007-09-09)
  [2844] Learning about Regular Expressions in C through examples - (2010-06-30)
  [3122] When is a program complete? - (2011-01-06)
  [3144] Setting up arrays in C - fixed size at compile time, or dynamic - (2011-01-24)
  [3146] Strings in C - (2011-01-25)
  [3593] Chars, char arrays and strings in C. Some early cautions and pitfalls. - (2012-01-26)
  [3718] Splitting a record into individual data values in C - (2012-05-04)
  [4340] Simple C structs - building up to full, dynamic example - (2014-12-03)
  [4556] Strings in C - strncmp strncpy and friends - (2015-10-27)
  [4633] String handling in C - new examples of extracting integers from a string - (2016-01-27)

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Catching up with an old friend
Objects and Inheritance in C++ - an easy start
String functions in C
Staring a C course with Hello World - why?
C Course exercise and sample answer - source in 2 files
Just pass a pointer - do not duplicate the data
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