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SF bug [#461674] struct 'p' format doesn't work (maybe)

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Rewrote the 'p' description.
This commit is contained in:
Tim Peters 2001-09-15 18:09:22 +00:00
parent e0007821cd
commit 88091aae7e
1 changed files with 11 additions and 7 deletions
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18
Doc/lib/libstruct.tex
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@ -94,13 +94,17 @@ For unpacking, the resulting string always has exactly the specified
number of bytes. As a special case, \code{'0s'} means a single, empty
string (while \code{'0c'} means 0 characters).
The \character{p} format character can be used to encode a Pascal
string. The first byte is the length of the stored string, with the
bytes of the string following. If count is given, it is used as the
total number of bytes used, including the length byte. If the string
passed in to \function{pack()} is too long, the stored representation
is truncated. If the string is too short, padding is used to ensure
that exactly enough bytes are used to satisfy the count.
The \character{p} format character encodes a "Pascal string", meaning
a short variable-length string stored in a fixed number of bytes.
The count is the total number of bytes stored. The first byte stored is
the length of the string, or 255, whichever is smaller. The bytes
of the string follow. If the string passed in to \function{pack()} is too
long (longer than the count minus 1), only the leading count-1 bytes of the
string are stored, If the string is shorter than count-1, it is padded
with null bytes so that exactly count bytes in all are used. Note that
for \function{unpack()}, the \character{p} format character consumes count
bytes, but that the string returned can never contain more than 255
characters.
For the \character{I}, \character{L}, \character{q} and \character{Q}
format characters, the return value is a Python long integer.