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Find a tag in the hwinfo structure


#include <hw/sysinfo.h>

unsigned hwi_find_tag( unsigned start, 
                       int curr_item, 
                       const char * tagname );


Where to start to search for the given item.

For the initial call, set this argument to HWI_NULL_OFF. If the item found isn't the one that you want, pass the return value from the first call to hwi_find_tag() as the start parameter of the next call. This makes the search pick up where it left off. You can repeat this process as many times as required (the return value from the second call going into the start parameter of the third, etc).

If this argument is nonzero, the search stops at the end of the current item (i.e. the one that start points to). If curr_item is zero, the search continues until the end of the section.
The name of tag to search for.



Use the -l c option to qcc to link against this library. This library is usually included automatically.

Note: This function is in libc.a, but not in (in order to save space).


The hwi_find_tag() function finds the tag named tagname.


The offset of the tag, or HWI_NULL_OFF if the tag wasn't found.


QNX Neutrino

Cancellation point No
Interrupt handler Yes
Signal handler Yes
Thread Yes

See also:

hwi_find_item(), hwi_off2tag(), hwi_tag2off()

Structure of the system page in the Customizing Image Startup Programs chapter of Building Embedded Systems