GNUPro® Toolkit GNUPro Development Tools

Interrupting or Killing the make Tool........................................................................118
Recursive Use of the make Tool................................................................................119
How the MAKE Variable Works ..............................................................................119
Communicating Variables to a Sub-make Utility...................................................120
Communicating Options to a Sub-make Utility .....................................................122
The --print-directory Option...........................................................................123
Defining Canned Command Sequences....................................................................124
Using Empty Commands ..........................................................................................125
How to Use Variables.................................................................................................127
Basics of Variable References ..................................................................................128
The Two Flavors of Variables ..................................................................................129
Substitution References .........................................................................................131
Computed Variable Names....................................................................................132
How Variables Get Their Values ..............................................................................134
Setting Variables .......................................................................................................135
Appending More Text to Variables ..........................................................................135
The override Directive............................................................................................137
Defining Variables Verbatim ....................................................................................137
Variables from the Environment...............................................................................138
Target-specific Variable Values................................................................................139
Pattern-specific Variable Values...............................................................................140
Conditional Parts of Makefiles..................................................................................141
Syntax of Conditionals..............................................................................................143
Conditionals That Test Flags ....................................................................................145
Functions for Transforming Text .............................................................................147
Function Call Syntax.................................................................................................148
Functions for String Substitution and Analysis ........................................................148
Functions for File Names..........................................................................................151
The foreach Function...............................................................................................153
The origin Function ................................................................................................155
The shell Function ..................................................................................................156
How to Run the make Tool .........................................................................................159
Arguments to Specify the Goals ...............................................................................160
Instead of Executing the Commands ........................................................................162
Avoiding Recompilation of Some Files....................................................................164
Overriding Variables.................................................................................................164
Testing the Compilation of a Program......................................................................165
Summary of make Options .........................................................................................167
Implicit Rules..............................................................................................................173
Using Implicit Rules .................................................................................................174
Catalogue of Implicit Rules ......................................................................................175
Variables Used by Implicit Rules .............................................................................179
viii ■ GNUPro Development Tools
Red Hat GNUPro Toolkit