Purpose: to document the various Tcl commands available to perform functions for which programmers commonly think they need external commands.
- clock instead of external commands for date or time
- glob instead of external commands for file listing commands like dir or ls
- file copy, delete, rename...
- open/read/close instead of external commands for reading files
- tcllib's fileutil has procs for cat, find, and grep
- while it isn't built in, see tail for info on doing basic 'read me the end of a file' type processing.
- auto_execok is handy for platform independant shell execution of commands.
See also What should I be sure to do so my Tcl based programs run cross platform
On the C level, see: Tcl Portable Runtime Library, which is the foundation to the Tcl level commands listed above.