7.4.5  
Character conversion functions
 
Character conversion functions are as follows.
Table 7.7  | Character Conversion Functions  | 
 
| 
 | 
 | 
| 
 
toupper 
 | 
 
Conversion from lower-case to upper-case (not converted if argument is not in lower-case) 
 | 
| 
 
tolower 
 | 
 
Conversion from upper-case to lower-case (not converted if argument is not in upper-case) 
 |