by Dinesh Thakur Category: Function and Pointer

Another commonly required string operation is that of converting the case of a given string. The C standard library does not provide any function for case conversion. However, some C implementations provide the strlwr and strupr functions. The strlwr function converts all characters in a given string to lowercase, whereas the strupr function converts all characters to uppercase. Typical calls to these functions take the following forms:

strlwr (s);

strupr (s);

Note that these functions modify the string passed as an argument and return a pointer to the modified string. The program segment given below converts (and prints) a string to uppercase and lowercase representations.

char str[] = "EVERYTHING is fair in LOVE and WAR";

printf("Uppercase: %s\n", strupr(str));

printf("Lowercase: %s\n", strlwr(str));

The output of this program segment is shown below.


Lowercase: everything is fair in love and war

About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.C.A, MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.

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