/* Jeffrin Jose Licensed GPL v3 Copyright August 2010 GPL –> http://www.gnu.org/copyleft/gpl.html */ #include #include int main() { int seconds; int i=0; char array[20]=”Happy Friendship Day”; /* printf(“n Happy Friendship Day n”); */ for(i=0;i<20;i++) { printf("%c",array[i]); /* for(seconds=0;seconds<100000000;seconds++);*/ /* system("sleep 1s");*/ fflush(stdout); sleep(1); } printf("\n"); for(i=0;i<20;i++) { printf("%c",'-'); /* for(seconds=0;seconds<100000000;seconds++);*/ /* system("sleep 1s");*/ fflush(stdout); usleep(100000); …
Author Archives: jeffrin
CMP . Instruction
WinDbg shows cmp Instruction 7c9011ec 803d94b0977c00 cmp byte ptr [ntdll!fltused+0x4c (7c97b094)],0 7c9011f3 8b7508 mov esi,dword ptr [ebp+8] 7c9011f6 8945fc mov dword ptr [ebp-4],eax 7c9011f9 0f85d7ec0000 jne ntdll!RtlInitUnicodeStringEx+0x61 (7c90fed6) 7c9011ff f6461010 test byte ptr [esi+10h],10h 7c901203 0f84cdec0000 je ntdll!RtlInitUnicodeStringEx+0x61 (7c90fed6) 7c901209 5e pop esi 7c90120a c9 leave 7c90120b c20400 ret 4 ntdll!DbgBreakPoint: 7c90120e cc int 3 …
Print With Delay 0.2
/* Jeffrin Jose Licensed GPL v3 Copyright August 2010 GPL –> http://www.gnu.org/copyleft/gpl.html */ #include #include int main() { int seconds; int i=0; char array[20]=”Happy Friendship Day”; /* printf(“n Happy Friendship Day n”); */ for(i=0;i<20;i++) { printf("%c",array[i]); /* for(seconds=0;seconds<100000000;seconds++);*/ /* system("sleep 1s");*/ fflush(stdout); sleep(1); } printf("\n"); return 0; }
fork example.
/* Jeffrin Jose <jeffrin@rocketmail.com> Licensed GPL v3 Copyright August 2010 GPL –> http://www.gnu.org/copyleft/gpl.html */ #include #include main() { /* fork(); */ printf(“nhellon”); fork(); printf(“n World n”); }
print with delay 0.1
/* Jeffrin Jose Licensed GPL v3 Copyright 2010 GPL –> http://www.gnu.org/copyleft/gpl.html */ #include #include int main() { int seconds; int i=0; char array[20]=”Happy Friendship Day”; /* printf(“n Happy Friendship Day n”); */ for(i=0;i<20;i++) { printf("%c",array[i]); /* for(seconds=0;seconds<100000000;seconds++);*/ /* system("sleep 1s");*/ sleep(1); /* Delay not Properly Implemented . FIXME. */ } printf("n"); return 0; }
exclusive OR Instruction :-
GDB shows XOR Instruction (gdb) disassemble 0x00007f16db50b647 Dump of assembler code for function gtk_main: 0x00007f16db50b5a0 : push %r15 0x00007f16db50b5a2 : xor %edi,%edi 0x00007f16db50b5a4 : mov $0x1,%esi 0x00007f16db50b5a9 : push %r14 0x00007f16db50b5ab : push %r13 0x00007f16db50b5ad : push %r12 0x00007f16db50b5af : push %rbp 0x00007f16db50b5b0 : push %rbx 0x00007f16db50b5b1 : sub $0x38,%rsp 0x00007f16db50b5b5 : addl $0x1,0x4e2af4(%rip) # …
square root = %f
/* Jeffrin Jose <jeffrin@rocketmail.com> Licensed GPL v3 Copyright 2010 GPL –> http://www.gnu.org/copyleft/gpl.html */ #include<stdio.h> main() { float x,y; printf(“\n Input an Integer :” ); scanf(“%f”,&x); y=sqrt (x); printf(” square root = %f”,y); getch(); }
software interrupt –
WinDbg shows “int” Instruction ntdll!DbgBreakPoint: 7c901230 cc int 3 7c901231 c3 ret 7c901232 8bff mov edi,edi ntdll!DbgUserBreakPoint: 7c901234 90 nop 7c901235 90 nop 7c901236 90 nop 7c901237 90 nop ntdll!DbgBreakPointWithStatus: 7c901238 90 nop ntdll!DbgUserBreakPoint: 7c901239 cc int 3 7c90123a c3 ret 7c90123b 90 nop 7c90123c 8bff mov edi,edi 7c901230 cc int 3 Process Involved WinRAR …
remainder 100/?
/* Jeffrin Jose <jeffrin@rocketmail.com> Licensed GPL v3 Copyright 2010 GPL –> http://www.gnu.org/copyleft/gpl.html */ #include<stdio.h> main () { int number,b; printf (“Enter a Number \n”); scanf(“%d”,&number); b=100%number; printf(“\n The Remainder with 100 = %d “,b); getch(); }
LEAVE Instruction ++
WinDbg shows “leave” instruction 7c901227 c9 leave 7c901228 c20400 ret 4 7c90122b 90 nop 7c90122c 90 nop 7c90122d 90 nop 7c90122e 90 nop 7c90122f 90 nop ntdll!DbgBreakPoint: 7c901230 cc int 3 7c901227 c9 leave Process Involved Program : “notepad” on Windows. Explanation LEAVE — High Level Procedure Exit LEAVE reverses the actions of the ENTER …