Linux basics

Week 1

D1 - File system, liscence, bootloader & boot process
D2 - Static & shared libraries
D3 - Makefile
D4 - Multithreading
D5

Week 2

D1 - Fork, wait_PID, system calls, process control, file manipulation
D2 -
D3 -
D4 -
D5 -

W1D1 - File structure

W1D2 - Static & shared libraries

Compile a simple .c code : gcc -o helloWorld helloWorld.c

We can also create libraries :

Static (.a)
- Create object file (compile library)
  
  src : lib_mylib.c
```
gcc -c lib_mylib.c -o lib_mylib.o
```
- Create static library
```
ar rcs lib_mylib.a lib_mylib.o
```
- Create a program using static library created
src : driver.c
```
gcc -c driver.c -o driver.o
```
- linked compiled progeam with static library
```
gcc -o driver driver.o -L. -l_mylib
```
[1]

Share or dynamic libraries (.so or .dll)

src : shared.c

gcc -o sample shared.c

ldd ./sample

linux-vdso.so.1 =>  (0x00007ffd880c1000)   
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007effbde40000)
/lib64/ld-linux-x86-64.so.2 (0x00007effbe20a000)

Here ldd perform a list dependencies of the programs binaries []

gcc -shared -fPIC -o liblibrary.so library.c
gcc application.c -L $(pwd)/ -llibrary -o sample_application
export LD_LIBRARY_PATH=$(pwd):$LD_LIBRARY_PATH

W1D3 - Makefile

W1D4 - Multhreading

#include <pthread.h>

gcc *.c -lpthread

Mutex

Can lock on only 1 resource

Semaphores

Can manage multiple resource

itsanjan/generic_c