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fmt_copybytes_sizeof_minus1(3) | Library Functions Manual | fmt_copybytes_sizeof_minus1(3) |
NAME¶
fmt_copybytes_sizeof_minus1 - write binary data
SYNTAX¶
#include <libowfat/fmt.h>
size_t fmt_copybytes_sizeof_minus1(char *dest,const char *source);
DESCRIPTION¶
This macro will copy sizeof(source)-1 bytes from source to dest.
This is a convenience wrapper interface around fmt_copybytes for the situation where you construct a binary message by concatenating hex constant strings like this:
fmt_copybytes_sizeof_minus1(dest, "\x01\x02\x03\x04");
Since the source is technically a string, the compiler will add a 0 byte and sizeof() will return the size including that 0 byte. That is why we have a minus 1 in this function, so we do not copy or count that 0 byte.
NOTE¶
Caution: source must not have side effects or those will be evaluated twice.