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C51: NON-REENTRANT PRINTF

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Information in this article applies to:

• C51 Version 5.50

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QUESTION

Is the printf() in the library reentrant or an ordinary routine? If it is a reentrant routine, is there a non-reentrant printf()?

ANSWER

printf() is non-reentrant. Caution must therefore be used when calling printf() in an ISR or other situations where printf() may be invoked while it is already executing.

MORE INFORMATION

• Refer to Stream I/O Routines in the Cx51 User's Guide.

SEE ALSO

• C51: CALLING PRINTF IN AN INTERRUPT
• RTX51: CALLING PRINTF FROM MULTIPLE TASKS

Last Reviewed: Friday, July 15, 2005

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