From: Craig Howland <howland@LGSInnovations.com>
To: <newlib@sourceware.org>
Subject: Re: printf() and _write() in newlib-nano
Date: Wed, 19 Apr 2017 15:17:00 -0000 [thread overview]
Message-ID: <f68eb55a-284c-aa70-af0f-e9e594546f11@LGSInnovations.com> (raw)
In-Reply-To: <02d116cb-f9a6-8f0c-8ab2-8dda8cec8f37@powersoft.it>
On 04/19/2017 04:55 AM, massimiliano cialdi wrote:
> I use newlib-nano in an embedded project.
> I have implemented my version of _write() to make printf() output chars to UART.
>
> I wonder if a single call of printf() results in a single call of _write(),
> or, otherwise _write() can be called more than once by printf().
>
> best regards
>
> Max
It depends on many factors (the actual print string, buffered, line buffered,
text mode, etc.), but either alternative can happen--either one _write per print
or more than one. It can range from one write per print to one per character.
If it is important to you, it probably would be best to instrument it to find
out directly, and you could observe how it varies.
prev parent reply other threads:[~2017-04-19 15:17 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-19 8:55 massimiliano cialdi
2017-04-19 15:17 ` Craig Howland [this message]
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