1. Programming in the Linux
Environment
ISO C and POSIX Standards
The Development tools
Using GCC
Creating and Using Libraries
Dynamic modules
Debugging with GDB

2. What are ISO C and POSIX
Standards and Why should we
care about them ?

3. The Development tools available in
the Linux Environment
– Programming Languages Available
✔ C
✔ C++
✔ Java
✔ Python
✔ C# (CLR comes from the Mono Project)
✔ Perl
✔ Tcl/tk
✔ Vala
✔ Lua
✔ Ada
✔ PHP
✔ Ruby
✔ Haskell, Pascal, Fortran, Lisp,

4. The Development tools available
in the Linux Environment
– Tools for C Programming
• GCC: GNU Compilers Collection
• GDB: GNU Debugger
• Emacs/Vi: The code editors

5. Using GCC
– Writing A “Hello World” Program
– Compiling and Running the program
gcc -o helloworld helloworld.c
./helloworld

6. Using GCC
– Some Essential features of GCC
• Including Additional Header Files
gcc -I/home/abhinav/code/include
include-test.c -o include-test
./include-test

7. Using GCC
– Some Essential features of GCC
• Linking Libraries
• Debugging symbols
• Creating libraries

8. Creating and Using Libraries
– Libraries are a collection of functions
– libm, libpthread, libdbm, libc
Types of Libraries:
– Static Libraries: .a extension
– Dynamic Libraries: .so extension

9. Creating and Using Libraries
– Making object files:
gcc -I./include -c new-helloworld.c print.c
– Linking Object files
• Gcc -o new-helloworld new-helloworld.o
print.o
-c : tells the compiler to only compile the
file, but not to link them
-o: to specify the name of the output file.

10. Creating and Using Libraries
– Creating Static Library:
• gcc -o *.c
• ar cr libcalc.a *.o
– Linking against the static library:
gcc -I./include -o calc-test calc-test.c -L.
-lcalc

11. Creating and Using Libraries
– Creating Shared Library:
• gcc -c -fPIC *.c
• gcc -shared -fPIC -o libcalc.so *.o
– Linking against the shared library:
(Same as linking against a static library)
gcc -I./include -o calc-test calc-test.c -L.
-lcalc

12. Debugging with GDB
– Generating debugging symbols:
• gcc -g -o
Starting the debugger:
• gdb <program name>
Some common commands:
• b line-number or function name: sets the break point
• next : step over
• step: step in
• p <variable name> : prints the value of the variable
• where: prints the stack trace
• up: moves you up in the stack

13. Dynamically Loading Modules
– Concept of Plugins/modules which are loaded by the program
at run tim
– No dynamic or statical linking of libraries
void *handle = dlopen(“libcalc.so”, RTLD_LAZY);
void (*test) () = dlsym(handle, “add”);
(*test) ();
dlclose (handle);

14. Some other productivity tools
Diff: What are the changes made in the file
Patch: merging the changes
Version Control tools: Git, Bazaar, mercurial, SVN, CVS

15. Thank You
--Abhinav Upadhyay
Twitter: iamabhi9
Irc.freenode.net: abhinav-