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[Static Library (How to Create)]

pico hello-1.c				-> get hello-1.c
gcc -c hello-1.c			-> get hello-1.o
ar -r hello-1.a hello-1.o		-> get hello-1.a (static library)
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[Static Library (How to Use)

pico main-1.c				-> get main-1.c
gcc -c main-1.c				-> get main-1.o
gcc -o main-1 main-1.o hello-1.a	-> get main-1
./main-1				-> execute main-1
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[Dynamic Library (How to Create)]

pico hello-2.c				-> get hello-2.c
gcc -c hello-2.c			-> get hello-2.o
gcc -shared -o libhello-2.so hello-2.o	-> get libhello-2.so (dynamic library)
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[Dynamic Library (How to Use)

pico main-2.c				-> get main-2.c
gcc -c main-2.c				-> get main-2.o
gcc -o main-2 main-2.o -L. -lhello-2	-> get main-2
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:.
./main-2				-> execute main-2
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[Some Notes]

1. gcc -c : compile only, don't link
2. gcc -shared : produce shared object
3. gcc -o filename : put output to the specified file
4. gcc -L path : specify the path to the shared library
5. gcc -l library : specify the name of the shared library
6. ar -r : insert file into the archive
7. export : set environment variables
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[hello-1.c]

#include <stdio.h>

void hello1(void){
  printf("Hello-1 (from static library hello-1.a)");
  printf("\n");
}
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[main-1.c]

int main(void){
  hello1();
  return(0);
}
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[hello-2.c]

#include <stdio.h>

void hello2(void){
  printf("Hello-2 (from dynamic library hello-2.so)");
  printf("\n");
}
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[main-2.c]

int main(void){
  hello2();
  return(0);
}
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[Reference]

http://www.experts-exchange.com/Programming/Programming_Languages/C/Q_20721083.html
http://www.linuxman.com.cy/rute/node26.html
http://gcc.gnu.org/onlinedocs/gcc-3.3.1/gcc/Overall-Options.html#Overall%20Options
http://gcc.gnu.org/onlinedocs/gcc-3.3.1/gcc/Link-Options.html#Link%20Options
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