Lab04 - Strings and (de)allocation

presentation

• use valgrind for memory leak detection
• can detect forgotten allocated memory and the exact location of out-of-bound access
• can report using uninitialized variables/memory
• for better output, compile your program with -g flag
• valgrind ./your-program

• https://en.cppreference.com/w/c
• learn to understand the function declaration (the name, return type, and parameters)
• the definition (code to be executed) might not always be available

• Remember you can use #include <string.h> for helper functions
• Let's declare an array of characters, and then ask the user for their first name
• Print the name, its length, and say if it's the same as your own name
• You can use the function strcmp to compare the strings, will return zero if the same

• Modify your program to use dynamic memory for the name
• Ask the user for other names
• Use realloc to make the original name string bigger
• Use memcpy to append the additional name to the original name/string

• Write a program which allows the user to enter “infinite” amounts of text, and will keep appending it to a string (char array).
• When they press enter, it will output the current string.
• If they enter a certain character, it will close.
• Use the getchar() function to get letters from the command line.
• You will need to use malloc() and realloc() to control the memory.
• Don’t forget to use free() at the end to free the memory.

• Update the previous code to read a whole word from the input.
• Implement your own version of the strcmp() function from the string.h library.
• Hard-code your name into your program, and ask the user to input words.
• If it matches your name, print a message!
• Can you make it case insensitive?

reference solutions