Name
pack
Synopsis
pack template, list
Description
Takes a list of values and packs it into a binary structure, returning the string containing the structure. The template is a sequence of characters that give the order and type of values, as follows:
| Character | Meaning |
|---|---|
a
| An ASCII string, will be null padded |
A
| An ASCII string, will be space padded |
b
| A bit string, low-to-high order (like vec()) |
B
| A bit string, high-to-low order |
c
| A signed char value |
C
| An unsigned char value |
d
| A double-precision float in the native format |
f
| A single-precision float in the native format |
h
| A hexadecimal string, low nybble first |
H
| A hexadecimal string, high nybble first |
i
| A signed integer value |
I
| An unsigned integer value |
l
| A signed long value |
L
| An unsigned long value |
n
| A short in “network” (big-endian) order |
N
| A long in “network” (big-endian) order |
p
| A pointer to a string |
P
| A pointer to a structure (fixed-length string) |
s
| A signed short value |
S
| An unsigned short value |
v
| A short in “VAX” (little-endian) order |
V
| A long in “VAX” (little-endian) order |
u
| A uuencoded string |
w
| A BER compressed integer |
x
| A null byte |
X
| Back up a byte |
@
| Null-fill to absolute position |
Each character may optionally be followed by a number that gives a repeat
count. Together the character and the repeat count make a field specifier.
Field specifiers may be separated by whitespace, which will be ignored. With
all types except a and A, the pack function will gobble up that many values from
the list. Saying * for the repeat count means ...
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