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  1. Commands
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strncmp

Description of the 'strncmp' function in HyperDbg Scripts

PreviousstrcmpNextwcscmp

Last updated 11 months ago

Function

strncmp

Syntax

strncmp( Str1, Str2, Num );

Parameters

[Str1]

A or a string to compare with Str2.

[Str2]

A or a string to compare with Str1.

[Num]

Maximum number of characters to compare.

Description

Compares up to Num characters of the string Str1 to the string Str2.

If the characters are equal, the comparison continues with the next pair of characters. This process repeats until the characters differ, a terminating null character is encountered, or Num characters have been compared in both strings, whichever occurs first.

Return value

Returns an integer value indicating the relationship between the strings:

Return Value
Indicates

<0

The first character that does not match has a lower value in Str1 than in Str2.

0

The contents of both strings are equal.

>0

The first character that does not match has a greater value in Str1 than in Str2.

Examples

strncmp(fffff806`6de00000, @rax+c0, 0n12);

Compare the the first 12 (decimal) characters of the string located at fffff806`6de00000 with the string located at @rax+c0.

strncmp(@rcx, "Test String", b);

Compare the first 0xb (hexadecimal) characters of the string located at @rcx with the string "Test String".

strncmp("Test String1", "Test String2", 0n7);

Compare the first 7 (decimal) characters of the string "Test String1" with the string "Test String2".

Remarks

This function checks for the validity of both the source and the destination address before the comparison.

The support for this function is added from v0.9.

Related

MASM-like expression
MASM-like expression
wcscmp
wcsncmp
memcmp