1.\" Copyright (c) 1989, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" @(#)toupper.3 5.1 (Berkeley) 05/02/91 5.\" %sccs.include.redist.man% 6.\" 7.\" @(#)toupper.3 5.1 (Berkeley) 05/02/91 8.\" 9.Dd 10.Dt TOUPPER 3 11.Os 12.Sh NAME 13.Nm toupper 14.Nd lower case to upper case letter conversion 15.Sh SYNOPSIS 16.Fd #include <ctype.h> 17.Ft int 18.Fn toupper "int c" 19.Sh DESCRIPTION 20The 21.Fn toupper 22function converts a lower-case letter to the corresponding 23upper-case letter. 24.SH RETURN VALUES 25If the argument is a lower-case letter, the 26.Fn toupper 27function returns the corresponding upper-case letter if there is 28one; otherwise the argument is returned unchanged. 29.\" In the 30.\" .Em ``C'' 31.\" locale, 32.\" .Fn toupper 33.\" maps only the characters for which 34.\" .Xr islower 35.\" is true to the corresponding characters for which 36.\" .Xr isupper 37.\" is true. 38.Sh SEE ALSO 39.Xr isascii 3 , 40.Xr isalnum 3 , 41.Xr isalpha 3 , 42.Xr iscntrl 3 , 43.Xr isdigit 3 , 44.Xr isgraph 3 , 45.Xr islower 3 , 46.Xr isprint 3 , 47.Xr ispunct 3 , 48.Xr isspace 3 , 49.Xr isupper 3 , 50.Xr isxdigit 3 , 51.Xr toascii 3 , 52.Xr toupper 3 , 53.Xr stdio 3 54.Xr ascii 7 55.Sh STANDARDS 56The 57.Fn tolower 58function conforms to 59.St -ansiC . 60