sprintf in C (pointer to an array of char elements) -

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i newbie in c, , want like

    uint8_t message[12];      message[0] = 0x00;     message[1] = 0x00;     message[2] = 0x00;     message[3] = 0x00;     message[4] = 0x00;     message[5] = 0x00;     message[6] = 0x00;     message[7] = 0x00;     message[8] = 0x00;     message[9] = 0x00;     message[10] = 0x00;     message[11] = 0x00;  sprintf(_smess,"at$ss=%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",                             message[0], message[1], message[2], message[3],                             message[4], message[5], message[6], message[7],                             message[8], message[9], message[10], message[11]);

but don't know how declare variable _smess, i've tried char *_smess or uint8_t _smess[12] got error anyway

if declare char _smess[43]; got error:

multiple markers @ line     - incompatible implicit declaration of built-in function 'sprintf' [enabled       default]     - implicit declaration of function 'sprintf' [-wimplicit-function-declaration]     - each undeclared identifier reported once each function       appears in     - '_smess' undeclared (first use in function)

you know how big string based on format string passed sprintf (i.e. 42 characters), declare char array of @ least size, making sure leave room nul ('\0') terminator:

char _smess[43];

edit:

the error "incompatible implicit declaration of built-in function 'sprintf'" because didn't #include <stdio.h> @ top of file.

the "'_smess' undeclared" error because didn't define before used. needs appear before sprintf call.


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