Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Programming
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Databases
Mail Systems
openSolaris
Eclipse Documentation
Techotopia.com
Virtuatopia.com

How To Guides
Virtualization
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Windows
Problem Solutions
Privacy Policy

  




 

 

[ < ] [ > ]   [ << ] [ Up ] [ >> ]         [Top] [Contents] [Index] [ ? ]

8.11 Functions That Control Make

These functions control the way make runs. Generally, they are used to provide information to the user of the makefile or to cause make to stop if some sort of environmental error is detected.

$(error text...)
Generates a fatal error where the message is text. Note that the error is generated whenever this function is evaluated. So, if you put it inside a command script or on the right side of a recursive variable assignment, it won't be evaluated until later. The text will be expanded before the error is generated.

For example,

 
ifdef ERROR1
$(error error is $(ERROR1))
endif

will generate a fatal error during the read of the makefile if the make variable ERROR1 is defined. Or,

 
ERR = $(error found an error!)

.PHONY: err
err: ; $(ERR)

will generate a fatal error while make is running, if the err target is invoked.

$(warning text...)
This function works similarly to the error function, above, except that make doesn't exit. Instead, text is expanded and the resulting message is displayed, but processing of the makefile continues.

The result of the expansion of this function is the empty string.



 
 
  Published under the terms of the GNU General Public License Design by Interspire