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fmt_asn1derlength(3) | Library Functions Manual | fmt_asn1derlength(3) |
NAME¶
fmt_asn1derlength - encode unsigned integer like ASN.1 DER length
SYNTAX¶
#include <libowfat/fmt.h>
size_t fmt_asn1derlength(char *dest,unsigned long long source);
DESCRIPTION¶
fmt_asn1derlength encodes an unsigned integer using the ASN.1 DER for encoding tag lengths. This can take from 1 byte (0-0x7f) up to sizeof(source)+1 bytes.
If dest equals FMT_LEN (i.e. is NULL), fmt_asn1derlength returns the number of bytes it would have written.
For convenience, fmt.h defines the integer FMT_ASN1LENGTH to be big enough to contain every possible fmt_asn1derlength output.