The following functions that are normally available to C programmers are simulated with script examples in this reference:

• isalnum()

• isalpha()

• iscntrl()

• isdigit()

• isgraph()

• islower()

• isprint()

• ispunct()

• isspace()

• isupper()

• isxdigit()

Strictly speaking, these functions should be coded to be aware of locale-specific issues. You may want to take example simulations provided here and modify them to your own needs to support that. These are just basic working examples.