# MUSL libc implementation

**URL:** <http://discourse.heig-vd.ch/t/musl-libc-implementation/271>\
**Category:** SO3 Operating System\
**Created:** [January 27, 2022, 9:02am UTC](http://discourse.heig-vd.ch/t/musl-libc-implementation/271 "2022-01-27T09:02:06Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![rossierd](http://discourse.heig-vd.ch/user_avatar/discourse.heig-vd.ch/rossierd/32/4_2.png) [@rossierd](http://discourse.heig-vd.ch/u/rossierd)\
**Post date:** [January 27, 2022, 9:02am UTC](http://discourse.heig-vd.ch/t/musl-libc-implementation/271/1 "2022-01-27T09:02:06Z")

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Recently, I’ve been asked to investigate the use of %0 formatter in printf which allows to have padding zeros before the number to display. For example,

> printf(“%04d”, 34);

will display 0034.

The MUSL libc does not support this formatter yet.