turkish-i

Your mission

Copy a string into dst, lowercasing the ASCII letters and leaving every other byte untouched.

today's brief

Turkish has a dotless i, so in a Turkish locale the capital I lowercases to a character that is not the ASCII i. Software that normalised user input by lowercasing it kept breaking the moment a phone was set to Turkish. Logins failed. One config parser decided INCLUDE was not INCLUDE. The fix everyone landed on was to stop being clever and only touch A to Z.

See it in action

lower_ascii(dst, "ILOVEYOU")

Expected result

iloveyou

Your checklist

For your own tracking. Tests grade your code.

dst has room for the whole string and its terminating zero.
A byte from A to Z is copied as the matching lowercase letter.
Every other byte is copied exactly as it is.
Terminate dst with a zero byte.

More examples

lower_ascii(dst, "Mixed-42_X")

Expected result

mixed-42_x

lower_ascii(dst, "")

Expected result

(empty result)

Constraints

Expected files

case.c

Allowed functions

None. Write every helper yourself.

Back to compete

Solutions

turkish-i

Your mission

Copy a string into dst, lowercasing the ASCII letters and leaving every other byte untouched.

today's brief

See it in action

lower_ascii(dst, "ILOVEYOU")

Expected result

iloveyou

Your checklist

For your own tracking. Tests grade your code.

dst has room for the whole string and its terminating zero.
A byte from A to Z is copied as the matching lowercase letter.
Every other byte is copied exactly as it is.
Terminate dst with a zero byte.

More examples

lower_ascii(dst, "Mixed-42_X")

Expected result

mixed-42_x

lower_ascii(dst, "")

Expected result

(empty result)

Constraints

Expected files

case.c

Allowed functions

None. Write every helper yourself.

Back to compete

Solutions