Re: [linux_var] Strano codice C

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Subject: Re: [linux_var] Strano codice C

From: Salvatore Racano <salvatoreracano@gmail.com>

Date: Tue, 22 May 2018 15:56:53 +0200

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Io so che è un metodo per raggruppare più istruzioni dentro una #define, senza avere poi un errore di compilazione durante l'uso.

vedi qui infatti:

https://stackoverflow.com/questions/257418/do-while-0-what-is-it-good-for

2018-05-22 15:32 GMT+02:00 Giovanni Orlandi <orlangio@gmail.com>:

Ciao,

in un file C di esempio ho trovato questo strano codice che mostro sotto:

#define handle_error(msg) do { perror(msg); exit(EXIT_FAILURE); } while (0)

A quanto capisco io il ciclo do { } while ( 0 ) viene eseguito sempre una sola volta,
ma a che cosa servirebbe ?
Forse ad evitare delle ottimizzazioni in sede di compilazione ?

Qualcuno lo sa ?
Giovanni

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Follow-Ups:

Re: [linux_var] Strano codice C
- From: Lorenzo Lobba <lorenzo.lobba@gmail.com>

References:

[linux_var] Strano codice C
- From: Giovanni Orlandi <orlangio@gmail.com>