1.\" Copyright (c) 1989, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the American National Standards Committee X3, on Information 6.\" Processing Systems. 7.\" 8.\" %sccs.include.redist.man% 9.\" 10.\" @(#)toupper.3 8.1 (Berkeley) 06/04/93 11.\" 12.Dd 13.Dt TOUPPER 3 14.Os 15.Sh NAME 16.Nm toupper 17.Nd lower case to upper case letter conversion 18.Sh SYNOPSIS 19.Fd #include <ctype.h> 20.Ft int 21.Fn toupper "int c" 22.Sh DESCRIPTION 23The 24.Fn toupper 25function converts a lower-case letter to the corresponding 26upper-case letter. 27.SH RETURN VALUES 28If the argument is a lower-case letter, the 29.Fn toupper 30function returns the corresponding upper-case letter if there is 31one; otherwise the argument is returned unchanged. 32.\" In the 33.\" .Em ``C'' 34.\" locale, 35.\" .Fn toupper 36.\" maps only the characters for which 37.\" .Xr islower 38.\" is true to the corresponding characters for which 39.\" .Xr isupper 40.\" is true. 41.Sh SEE ALSO 42.Xr isascii 3 , 43.Xr isalnum 3 , 44.Xr isalpha 3 , 45.Xr iscntrl 3 , 46.Xr isdigit 3 , 47.Xr isgraph 3 , 48.Xr islower 3 , 49.Xr isprint 3 , 50.Xr ispunct 3 , 51.Xr isspace 3 , 52.Xr isupper 3 , 53.Xr isxdigit 3 , 54.Xr toascii 3 , 55.Xr toupper 3 , 56.Xr stdio 3 57.Xr ascii 7 58.Sh STANDARDS 59The 60.Fn tolower 61function conforms to 62.St -ansiC . 63