How does dynamic memory allocation work for strings?

In programming, strings can be stored using static allocation with a predetermined maximum length or dynamic allocation to handle a variable number of elements. Languages like C handle manual dynamic memory management through standard library functions such as malloc, realloc, calloc, and free. Different implementations of these allocation mechanisms can vary significantly in execution time and memory efficiency.

What we know

• A string can be implemented as an array data structure of bytes or words that stores a sequence of characters using character encoding. [3]
• Depending on the programming language and data type, string variables may use static storage for a predetermined maximum length or dynamic allocation for a variable number of elements. [3]
• In C, manual memory management for dynamic allocation is performed via standard library functions including malloc, realloc, calloc, aligned_alloc, and free. [2]
• Many different implementations of the actual memory allocation mechanism used by malloc are available, with performance varying in execution time and required memory. [2]

Where to go next

• compared withWhat are the differences between malloc and new in C++?
• how it workedHow does Rust enforce memory safety without a garbage collector?
• whenWhat is the history of the C programming language?
• the bigger pictureHow are character encodings handled in string data structures?
• what followedWhat are the performance characteristics of different malloc implementations?
• an unexpected connectionHow does Dennis Ritchie's creation of C relate to modern memory safety?Dennis Ritchie designed C to give direct access to CPU architectures with minimal runtime support, which later necessitated advanced compilation tools like Rust's borrow checker to prevent memory safety errors.

Sources

• [1]C dynamic memory allocation (Wikidata Q1050390) · CC0 1.0
• [2]C dynamic memory allocation · CC BY-SA 4.0
• [3]String (computer science) · CC BY-SA 4.0
• [4]C (programming language) · CC BY-SA 4.0
• [5]Rust (programming language) · CC BY-SA 4.0