2011-05-18 02:03:47     Any special care needed for MMU-less and fork-less programming ?

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2011-05-18 02:03:47     Any special care needed for MMU-less and fork-less programming ?

Faclon Seventy4 (INDIA)

Message: 100710   

 

Hi,

 

Have been programming on/around Linux for several years, but just getting introduced to uClinux, and reading through some initial material find that 2 clear distinguishing feature of uCLinux (compared to regular Linux) are:-

 

1) Lack of MMU support (i.e. everything limited to physical memory, and no virtual memory -- if I understood it right)

 

2) Not able to fork. This is something gathered from a forum post, but don't quite understand how the system startsup if there is no fork() or vfork() support. Is this true ?

 

Any pointers on uCLinux programming, and especially something which makes the regular Linux to uCLinux transition easy for programmers.

 

Also, are there some special "tricks" / advice on porting current Linux applications that probably assume availability of very large memory space (served using virtual memory). I am assuming that the porting will involve some in-program memory-management (all done in software).

 

Pointers / guidance would be really helpful.

 

cheers,

F

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2011-05-18 02:36:29     Re: Any special care needed for MMU-less and fork-less programming ?

Mike Frysinger (UNITED STATES)

Message: 100712   

 

vfork exists and that's what everything uses

 

please review the wiki:

  docs.blackfin.uclinux.org/doku.php?id=porting_applications

  docs.blackfin.uclinux.org/doku.php?id=living_without_forks

  docs.blackfin.uclinux.org/doku.php?id=uclinux-dist:difference_from_linux

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