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Platforms
©2000-2008 Tibbo Technology Inc.
Syntax:
sha1(byref str as string,byref input_hash as string,
sha1_mode as sha1_modes,total_len as word) as
string
Returns:
20-character hash string; an empty string when invalid
str or input_hash argument was detected
See Also:
Part
Description
str
String containing (the next portion of) the input data to
generate SHA1 hash on. When sha1_mode= 0-
SHA1_UPDATE, this string must be 64, 128, or 192
characters in length. Any other length will result in error
and the function will return an empty string. When
sha1_mode= 1- SHA1_FINISH, this string can have any
length (up to 255 bytes).
input_hash
Hash obtained as a result of SHA1 calculation on the
previous data portion. Leave it empty for the first portion of
data. Use the result of SHA1 calculation on the previous
data portion for the second and all subsequent portions of
data. The result of sha1 is always 20 characters long, so
passing the string of any other length (except 0 -- see
above) will result in error and this function will return an
empty string.
sha1_mode
0- SHA1_UPDATE : Set this mode for all data portions
except the last one.
1- SHA1_FINISH: Set this mode for the last data portion;
also use this selection if you only have a single data
portion.
total_len
Total length of processed data (in all data portions
combined). Only relevant when sha1_mode= 1-
SHA1_FINISH. That is, only relevant for the last or a single
data portion.
Details
SHA1 is a standard method of calculating hash codes on data of any size. The
amount of input data can often exceed maximum capacity of string variables (255
characters). The sha1 method can be invoked repeatedly in order to process the
data of any size (see the example below).
Examples
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