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byte_starts(3)		   Library Functions Manual		byte_starts(3)

NAME
       byte_starts - find out if a buffer starts with a	string

SYNTAX
       #include	<libowfat/byte.h>

       int byte_starts(const char *buf,size_t buflen,const char	*str);

DESCRIPTION
       byte_starts   returns  1	 if  the  buflen>=strlen(str)  and  the	 first
       strlen(str) bytes of buf	match the contents of str, or 0	otherwise.

       This function is	meant to be used in protocol parsing and with a	string
       constant	for str	and will use gcc/clang macro trickery to reduce	 to  a
       call to memcmp then.

       byte_starts  compares  as  few bytes as possible. An attacker observing
       the execution timing can	thus learn where the first mismatch happened.

       Use byte_equal_notimingattack to	compare	keys, passphrases, cookies  or
       hashes instead.

SEE ALSO
       byte_equal(3), byte_equal_notimingattack(3), byte_start(3)

								byte_starts(3)

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