●●● ●●●● 4.3 Thread libraries ●●●●● ●●● ●●●0● ●●●0 Thread library provides the programmer an API for creating and managing threads Two primary ways of implementing o Library entirely in user space All code and data structures for the library exist in user space Invoking a function in library results in a local function call in user space and not a system call o Kernel-level library supported by the os All code and data structures for the library exist in kernel space Invoking a function in library results in a local function call in a system call to the kernel20 4.3 Thread Libraries ⚫ Thread library ⚫ provides the programmer an API for creating and managing threads ⚫ Two primary ways of implementing ⚫ Library entirely in user space ▪ All code and data structures for the library exist in user space ▪ Invoking a function in library results in a local function call in user space and not a system call ⚫ Kernel-level library supported by the OS ▪ All code and data structures for the library exist in kernel space ▪ Invoking a function in library results in a local function call in a system call to the kernel