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completion definitions dans eadme

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hugogogo
2021-12-29 10:15:59 +01:00
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@@ -8,39 +8,43 @@ options :
``` ```
thread : thread :
- thread are light-weight-process (LWP) that happens inside a process - parts of a process that performs code simultaneously
- thread are light-weight-process (LWP) that happens inside a process (observe with command `ps -eLf`)
- a process can be single-threaded or multi-threaded - a process can be single-threaded or multi-threaded
- different process have a unique PID with a unique LWP, different thread in the same process have the same PID and a different LWP - different process have a different PID and different LWP, different thread in the same process have the same PID and different LWP
- thread vs process : - thread vs process :
process : process :
- process is isolated, it doesn't share memory with any other process - process is isolated, it doesn't share memory with any other process
- process can have states : new, ready, running, waiting, terminated, suspended
- process is less efficient in communication, it takes more times to create or terminate or switch - process is less efficient in communication, it takes more times to create or terminate or switch
- process speed is not impacted by speed of other process (untill it reach the limit of cpu) - process speed is not impacted by speed of other process (untill it reach the limit of cpu)
- process are created with fork() and execve() (to duplicate a process in a child process, or replacing an existing process)
thread : thread :
- thread are not isolated - thread are not isolated, they share memory with the other threads
- thread can have states : running, ready, blocked
- thread is more efficient in communication, it takes less times to create or terminate or switch - thread is more efficient in communication, it takes less times to create or terminate or switch
- thread can become slow if the process does many concurrent tasks - thread can become slow if the process does many concurrent tasks
- ressources : - ressources :
- https://www.baeldung.com/linux/process-vs-thread - https://www.baeldung.com/linux/process-vs-thread
mutex :
- mutual exclusion
- to prevent a part of the code to be performed simultaneously by threads
- the section of code wraped by a mutex can be access by only one thread at a time
- the section starts by unlocking a mutex, and end by locking it
external function : external function :
- `memset` : fill memory with a constant byte - `memset` : fill memory with a constant byte
- `printf` : format and print data - `printf` : format and print data
- `malloc` : allocate dynamic memory - `malloc` : allocate dynamic memory
- `free` : free dynamic memory - `free` : free dynamic memory
- `write` : write to a file descriptor - `write` : write to a file descriptor
- `usleep` : suspend execution for microseconds intervals - `usleep` : suspend execution for microseconds intervals
- `gettimeofday` : get time - `gettimeofday`: get time
- `pthread_create` : create a new thread - `pthread_create` : create a new thread
- `pthread_detach` : - `pthread_join` : wait for a thread to finish,
- `pthread_join` - `pthread_detach` : when a thread is detached it cannot be join, you cannot wait for it to teminate, it will release its ressources on its own when it has finish
- `pthread_mutex_init` - `pthread_mutex_init` : initialize a mutex
- `pthread_mutex_destroy` - `pthread_mutex_destroy`: destroy a mutex
- `pthread_mutex_lock` - `pthread_mutex_unlock` : unlock a mutex
- `pthread_mutex_unlock` - `pthread_mutex_lock` : lock a mutex