/usr/share/zsh/5.5.1/help
Edit: /usr/share/zsh/5.5.1/help/zcompile (6629B)
zcompile [ -U ] [ -z | -k ] [ -R | -M ] file [ name ... ]
zcompile -ca [ -m ] [ -R | -M ] file [ name ... ]
zcompile -t file [ name ... ]
This builtin command can be used to compile functions or
scripts, storing the compiled form in a file, and to examine
files containing the compiled form. This allows faster
autoloading of functions and sourcing of scripts by avoiding
parsing of the text when the files are read.
The first form (without the -c, -a or -t options) creates a com-
piled file. If only the file argument is given, the output file
has the name `file.zwc' and will be placed in the same directory
as the file. The shell will load the compiled file instead of
the normal function file when the function is autoloaded; see
the section `Autoloading Functions' in zshmisc(1) for a descrip-
tion of how autoloaded functions are searched. The extension
.zwc stands for `zsh word code'.
If there is at least one name argument, all the named files are
compiled into the output file given as the first argument. If
file does not end in .zwc, this extension is automatically
appended. Files containing multiple compiled functions are
called `digest' files, and are intended to be used as elements
of the FPATH/fpath special array.
The second form, with the -c or -a options, writes the compiled
definitions for all the named functions into file. For -c, the
names must be functions currently defined in the shell, not
those marked for autoloading. Undefined functions that are
marked for autoloading may be written by using the -a option, in
which case the fpath is searched and the contents of the defini-
tion files for those functions, if found, are compiled into
file. If both -c and -a are given, names of both defined func-
tions and functions marked for autoloading may be given. In
either case, the functions in files written with the -c or -a
option will be autoloaded as if the KSH_AUTOLOAD option were
unset.
The reason for handling loaded and not-yet-loaded functions with
different options is that some definition files for autoloading
define multiple functions, including the function with the same
name as the file, and, at the end, call that function. In such
cases the output of `zcompile -c' does not include the addi-
tional functions defined in the file, and any other initializa-
tion code in the file is lost. Using `zcompile -a' captures all
this extra information.
If the -m option is combined with -c or -a, the names are used
as patterns and all functions whose names match one of these
patterns will be written. If no name is given, the definitions
of all functions currently defined or marked as autoloaded will
be written.
Note the second form cannot be used for compiling functions that
include redirections as part of the definition rather than
within the body of the function; for example
fn1() { { ... } >~/logfile }
can be compiled but
fn1() { ... } >~/logfile
cannot. It is possible to use the first form of zcompile to
compile autoloadable functions that include the full function
definition instead of just the body of the function.
The third form, with the -t option, examines an existing com-
piled file. Without further arguments, the names of the origi-
nal files compiled into it are listed. The first line of output
shows the version of the shell which compiled the file and how
the file will be used (i.e. by reading it directly or by mapping
it into memory). With arguments, nothing is output and the
return status is set to zero if definitions for all names were
found in the compiled file, and non-zero if the definition for
at least one name was not found.
Other options:
-U Aliases are not expanded when compiling the named files.
-R When the compiled file is read, its contents are copied
into the shell's memory, rather than memory-mapped (see
-M). This happens automatically on systems that do not
support memory mapping.
When compiling scripts instead of autoloadable functions,
it is often desirable to use this option; otherwise the
whole file, including the code to define functions which
have already been defined, will remain mapped, conse-
quently wasting memory.
-M The compiled file is mapped into the shell's memory when
read. This is done in such a way that multiple instances
of the shell running on the same host will share this
mapped file. If neither -R nor -M is given, the zcompile
builtin decides what to do based on the size of the com-
piled file.
-k
-z These options are used when the compiled file contains
functions which are to be autoloaded. If -z is given, the
function will be autoloaded as if the KSH_AUTOLOAD option
is not set, even if it is set at the time the compiled
file is read, while if the -k is given, the function will
be loaded as if KSH_AUTOLOAD is set. These options also
take precedence over any -k or -z options specified to
the autoload builtin. If neither of these options is
given, the function will be loaded as determined by the
setting of the KSH_AUTOLOAD option at the time the com-
piled file is read.
These options may also appear as many times as necessary
between the listed names to specify the loading style of
all following functions, up to the next -k or -z.
The created file always contains two versions of the com-
piled format, one for big-endian machines and one for
small-endian machines. The upshot of this is that the
compiled file is machine independent and if it is read or
mapped, only one half of the file is actually used (and
mapped).