Examples of System Functions Disassmebling
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;htons, Ord 9, Addr = 71AB1746 (Function Entry Point)
;     Ord 15, Addr = 71AB1746 (Function Entry Point)
71AB1746  0F B7 44 24 04          MOVZX   EAX,WORD PTR [ESP+04]
71AB174B  33 C9                   XOR     ECX,ECX
71AB174D  8A E8                   MOV     CH,AL
71AB174F  C1 E8 08                SHR     EAX,08
71AB1752  0B C8                   OR      ECX,EAX
71AB1754  66 8B C1                MOV     AX,CX
71AB1757  C2 04 00                RET     0004


;IsDebuggerPresent, Ord 548, Addr = 77E72740 (Function Entry Point)
77E72740  64                      FS:
77E72741  A1 18 00 00 00          MOV     EAX,[00000018]
77E72746  8B 40 30                MOV     EAX,[EAX+30]
77E72749  0F B6 40 02             MOVZX   EAX,BYTE PTR [EAX+02]
77E7274D  C3                      RET     


;memset, Ord 1364, Addr = 77F784D0 (Function Entry Point)
77F784D0  8B 54 24 0C             MOV     EDX,[ESP+0C]
77F784D4  8B 4C 24 04             MOV     ECX,[ESP+04]
77F784D8  85 D2                   TEST    EDX,EDX
77F784DA  74 47                   JZ      77F78523
77F784DC  33 C0                   XOR     EAX,EAX
77F784DE  8A 44 24 08             MOV     AL,[ESP+08]
77F784E2  57                      PUSH    EDI
77F784E3  8B F9                   MOV     EDI,ECX
77F784E5  83 FA 04                CMP     EDX,04
77F784E8  72 2D                   JB      77F78517
77F784EA  F7 D9                   NEG     ECX
77F784EC  83 E1 03                AND     ECX,03
77F784EF  74 08                   JZ      77F784F9
77F784F1  2B D1                   SUB     EDX,ECX
77F784F3  88 07                   MOV     [EDI],AL
77F784F5  47                      INC     EDI
77F784F6  49                      DEC     ECX
77F784F7  75 FA                   JNZ     77F784F3
77F784F9  8B C8                   MOV     ECX,EAX
77F784FB  C1 E0 08                SHL     EAX,08
77F784FE  03 C1                   ADD     EAX,ECX
77F78500  8B C8                   MOV     ECX,EAX
77F78502  C1 E0 10                SHL     EAX,10
77F78505  03 C1                   ADD     EAX,ECX
77F78507  8B CA                   MOV     ECX,EDX
77F78509  83 E2 03                AND     EDX,03
77F7850C  C1 E9 02                SHR     ECX,02
77F7850F  74 06                   JZ      77F78517
77F78511  F3                      REPZ 
77F78512  AB                      STOSD
77F78513  85 D2                   TEST    EDX,EDX
77F78515  74 06                   JZ      77F7851D
77F78517  88 07                   MOV     [EDI],AL
77F78519  47                      INC     EDI
77F7851A  4A                      DEC     EDX
77F7851B  75 FA                   JNZ     77F78517
77F7851D  8B 44 24 08             MOV     EAX,[ESP+08]
77F78521  5F                      POP     EDI
77F78522  C3                      RET     
77F78523  8B 44 24 04             MOV     EAX,[ESP+04]
77F78527  C3                      RET