Compares at mostcount characters of two possibly null-terminated arrays. The comparison is done lexicographically. Characters following the null character are not compared.

The sign of the result is the sign of the difference between the values of the first pair of characters (both interpreted asunsignedchar) that differ in the arrays being compared.

The behavior is undefined when access occurs past the end of either arraylhs orrhs. The behavior is undefined when eitherlhs orrhs is the null pointer.

[edit]Parameters

[edit]Return value

Negative value iflhs appears beforerhs in lexicographical order.

Zero iflhs andrhs compare equal, or if count is zero.

Positive value iflhs appears afterrhs in lexicographical order.

[edit]Notes

This function is not locale-sensitive, unlikestrcoll andstrxfrm.

[edit]Example

#include <stdio.h>#include <string.h> void demo(constchar* lhs,constchar* rhs,int sz){constint rc= strncmp(lhs, rhs, sz);if(rc<0)printf("First %d chars of [%s] precede [%s]\n", sz, lhs, rhs);elseif(rc>0)printf("First %d chars of [%s] follow [%s]\n", sz, lhs, rhs);elseprintf("First %d chars of [%s] equal [%s]\n", sz, lhs, rhs);}int main(void){constchar* string="Hello World!";    demo(string,"Hello!",5);    demo(string,"Hello",10);    demo(string,"Hello there",10);    demo("Hello, everybody!"+12,"Hello, somebody!"+11,5);}

First 5 chars of [Hello World!] equal [Hello!]First 10 chars of [Hello World!] follow [Hello]First 10 chars of [Hello World!] precede [Hello there]First 5 chars of [body!] equal [body!]

[edit]References

[edit]See also

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