The Tcl library , a part of the Tcl core distribution , is a collection of procedures for commonly needed functions .
- official reference
- determines whether an executable file, or shell builtin, exists
- search for and load definitions for commands matching a specified patttern
- attempts to load the definition for a command
- generates an index suitable for use by auto_load , writing it to a file name tclIndex
- computes a list of fully-qualified names for a command
- destroys all the information cached by auto_execok and auto_load
- prints the names and values of the elments in an array
- a standard search procedure used by extensions during their initialization
- find the end of the specified word
- find the start of the next word
- find the start of the previous word
- find the beginning of word delimiter after the specified word
- find the beginning of the word delimiter before the specified word
The following global variables are defined or used by the procedures in the Tcl library .
- an array containing the names of commands that could not be located by auto_execok
- an array of names of commands known to auto_load
- If this variable is defined , unknown will not attempt to exec any unknown commands .
- If this variable is defined , unknown will not attempt to auto_load any commands
- a list of directories that package unknown searches to find package packages . The initial value of this variable aggregated from the value of the following sources , in order : $env(TCLLIBPAHT) , $tcl_library , the parent directory of $tcl_library , and $tcl_pkgPath .
- tcl_wordchars and tcl_nonwordchars
- Used by $tcl_endOfWord , tcl_startOfNextWord , tcl_startOfPreviousWord , tcl_wordBreakAfter , and tcl_wordBreakBefore commands . By default , these variables are not defined and the following rules apply: Under Unix , word characters are numbers , letters , and underscores ; under Windows , word characters are every character except space , tab , and newline .