Since all data in Tcl is either a string or an array which maps strings to strings, it should not be surprising that there are lots of commands for working with strings.

The first section in this chapter covers the string action family. This family views strings as sequences of characters. Other built-in commands deal with strings from other points of view. To mention two: there are commands in the previous chapter that view strings as lists and there are commands in the next chapter that view strings as potential matches for regular-expression patterns.

This chapter describes several useful action families. All of these action families make use of strings and all make use of glob pattern matching which is a topic deserving of its own section.

• The string Action Family
• The file Action Family
• The info Action Family
• Glob Patterns
• Commands Accepting Glob Patterns
• Developing for Multiple Platforms
• A Statistical Example
• Solutions to Exercises