■ Purpose : Create a C program, compile it, apply patch to original file
■ OS Environemnt : Linus
■ Required Software : gcc
■ Implementation Steps :
1. Create a test.c file and put below codes in it :
#include
#include
int main()
{
printf("\n I'm test\n");
return 0;
}
2. Compile above file and check its output :
$ gcc -o test test.c
$ ./test
I'm test
3. Applying patches or change codes and recompile it :
Modify test.c and add new lines or codes in it. Lets say new file is test_modifed.c. This file contains following codes :
#include
#include
int main()
{
printf("\n I'm kamal \n");
printf("\nI have added one more line. This comes from modifed code\n" );
return 0;
}
Compile & execute above program now :
$ gcc -o test_modified test_modified.c
$ ./test_modified
I'm test
I have added one more line. This comes from modifed code
4. Create a patch file :
Execute following command to create a patch in the same directory. :
$ diff -u test.c test_modified.c > test.patch.1
Here test.path.1 will contain following :
$ cat test.patch.1
--- test.c 2012-07-17 07:52:39.000000000 +0530
+++ test_modified.c 2012-07-17 07:54:41.000000000 +0530
@@ -3,5 +3,6 @@
int main()
{
printf("\n I'm kamal \n");
+ printf("\nI have added one more line. This comes from modifed code\n" );
return 0;
}
5. Applying above patch to original file :
$ patch -u test.c < test.patch.1
patching file test.c
$ cat test.c
#include
#include
int main()
{
printf("\n I'm kamal \n");
printf("\nI have added one more line. This comes from modifed code\n" );
return 0;
}
6. Reverting back to previous version :
$ patch -R test.c < test.patch.1
patching file test.c
$ cat test.c
#include
#include
int main()
{
printf("\n I'm kamal \n");
return 0;
}
7. Dry run : You can do dry-run (test prior to be originally changing codes in test.c)
$ patch -p0 --dry-run test.c < test.patch.1
■ OS Environemnt : Linus
■ Required Software : gcc
■ Implementation Steps :
1. Create a test.c file and put below codes in it :
#include
#include
int main()
{
printf("\n I'm test\n");
return 0;
}
2. Compile above file and check its output :
$ gcc -o test test.c
3. Applying patches or change codes and recompile it :
Modify test.c and add new lines or codes in it. Lets say new file is test_modifed.c. This file contains following codes :
#include
#include
int main()
{
printf("\n I'm kamal \n");
printf("\nI have added one more line. This comes from modifed code\n" );
return 0;
}
Compile & execute above program now :
$ gcc -o test_modified test_modified.c
$ ./test_modified
I'm test
I have added one more line. This comes from modifed code
4. Create a patch file :
Execute following command to create a patch in the same directory. :
$ diff -u test.c test_modified.c > test.patch.1
Here test.path.1 will contain following :
$ cat test.patch.1
--- test.c 2012-07-17 07:52:39.000000000 +0530
+++ test_modified.c 2012-07-17 07:54:41.000000000 +0530
@@ -3,5 +3,6 @@
int main()
{
printf("\n I'm kamal \n");
+ printf("\nI have added one more line. This comes from modifed code\n" );
return 0;
}
5. Applying above patch to original file :
$ patch -u test.c < test.patch.1
patching file test.c
$ cat test.c
#include
#include
int main()
{
printf("\n I'm kamal \n");
printf("\nI have added one more line. This comes from modifed code\n" );
return 0;
}
6. Reverting back to previous version :
$ patch -R test.c < test.patch.1
patching file test.c
#include
#include
int main()
{
printf("\n I'm kamal \n");
return 0;
}
7. Dry run : You can do dry-run (test prior to be originally changing codes in test.c)
$ patch -p0 --dry-run test.c < test.patch.1
