Incrementing a pointer variable's address increases its value by the size of the data type the pointer references. To assign a pointer the address of an array, the ampersand isn't required. Incrementing a pointer referencing an array, sets the pointer to the next element in the array. The sizeof operator obtains the number of bytes used by a variable stored in memory.
- [Instructor] A pointer is a variable … that holds a memory location. … So, what happens when you add one to that variable? … And I'm referring to the pointer variable … as an address, without the asterisk. … As an example in this exercise file you see pointer "pa" … initialized to the address of variable "alpha" in line 8. … Both are integer variables. Line 9 displays the address … stored in pa, and line 10 displays that address plus 1. … Build and run. … Now, using my best hexadecimal math … I can tell you that these two values differ by 4 bites. … 8 is 4 bites away from C. … Adding 1 to the address stored in pa … Increased that address by 4 bites. … By the way, at this point in line 10 … the pointer references some unknown chunk of memory … this unsafe coding practice, but I did it here … to illustrate a point. … Here's a better example. … In this exercise file aray twos is defined … and pointer pt is set to the base address … of the array at line 8. … No ampersand is required with this assignment …
Author
Dan Gookin
Released
5/1/2019- Working with arrays
- Building a structure
- Creating an array of structures
- Testing characters
- Working with strings in C
- Using pointers to manipulate data
- Manipulating files
- Using command-line arguments
- Working with time functions
Skill Level Intermediate
Duration
Views
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Introduction
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Using the exercise files1m 23s
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Configuring the IDE2m 34s
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1. Arrays and Structures
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Understanding arrays2m 59s
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Working with arrays3m 5s
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Modifying arrays3m 11s
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Building a structure3m 23s
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Nesting structures2m 56s
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Understanding a union2m 47s
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2. Characters and Strings
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Testing characters2m 34s
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Fetching string input3m 18s
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Sending string output2m 46s
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Using printf() placeholders3m 36s
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Exploring string functions3m 29s
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Manipulating strings3m 53s
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Avoiding string problems2m 27s
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3. Pointers
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Understanding pointers3m 19s
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Doing pointer math2m 57s
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Allocating storage3m 15s
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Working with a pointer array3m 38s
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Using pointers in structures3m 30s
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Returning pointers2m 39s
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4. Files and the Operating System
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Reading from a file3m 25s
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Writing to a file3m 24s
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Working with raw data2m 53s
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Using random file access2m 47s
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Manipulating files2m 57s
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Exploring the path2m 8s
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Reading a directory2m 53s
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Getting file information2m 46s
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Using command line arguments2m 44s
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Calling the operating system2m 46s
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5. The Interesting and Extraordinary
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Solving math puzzles3m 32s
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Creating random numbers3m 42s
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Working with time functions3m 54s
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Sorting data4m 8s
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Using a debugger4m 53s
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Writing your own header file2m 53s
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Challenge: Lotto simulation1m 18s
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Solution: Lotto simulation2m 29s
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Conclusion
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Next steps1m 52s
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Video: Doing pointer math