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$(node sequence) : File Sequence
sequence : Sequence
$(file sequence) : File Sequence
sequence : Sequence
$(dir sequence) : Dir Sequence
sequence : Sequence
The node, file, and dir functions define location-independent references to files and directories.
In omake, the commands to build a target are executed in the target's directory. Since there may be
many directories in an omake project, the build system provides a way to construct a reference to a file
in one directory, and use it in another without explicitly modifying the file name. The functions have the following
syntax, where the name should refer to a file or directory.
For example, we can construct a reference to a file foo in the current directory.
FOO = $(file foo) .SUBDIRS: bar
If the FOO variable is expanded in the bar subdirectory, it will expand to ../foo.
These commands are often used in the top-level OMakefile to provide location-independent references to top-level directories, so that build commands may refer to these directories as if they were absolute.
ROOT = $(dir .) LIB = $(dir lib) BIN = $(dir bin)
Once these variables are defined, they can be used in build commands in subdirectories as follows, where
$(BIN) will expand to the location of the bin directory relative to the command being executed.
install: hello cp hello $(BIN)
The node function is like the file function except that names of .PHONY
targets are more permissive. The file function requires an explicit qualifier,
the node function does not.
osh> .PHONY: foo osh> file(foo) - : .../foo : File osh> file(.PHONY/foo) - : <phony <.../foo>> : File osh> node(foo) - : <phony <.../foo>> : File
$(file-type nodes) : String Array
files : Node Array
The function file-type lists the type of node, as one of the
following entries.
.PHONY).
:optional: dependency.
:exists: dependency.
:squash: dependency.
.SCANNER).
$(tmpfile prefix) : File
$(tmpfile prefix, suffix) : File
prefix : String
suffix : String
The tmpfile function returns the name of a fresh temporary file in
the temporary directory.
$(in dir, exp) : String Array
dir : Dir
exp : expression
The in function is closely related to the dir and
file functions. It takes a directory and an expression, and
evaluates the expression in that effective directory.
For example, one common way to install a file is to define a symbol link, where the
value of the link is relative to the directory where the link is created.
The following commands create links in the $(LIB) directory.
FOO = $(file foo)
install:
ln -s $(in $(LIB), $(FOO)) $(LIB)/foo
Note that the in function only affects the expansion of Node
(File and Dir) values.
$(basename files) : String Sequence
files : String Sequence
The basename function returns the base names for a list of files.
The basename is the filename with any leading directory components removed.
For example, the expression $(basename dir1/dir2/a.out /etc/modules.conf /foo.ml) evaluates to
a.out modules.conf foo.ml.
$(dirname files) : String Sequence
files : String Sequence
The dirname function returns the directory name for a list of files.
The directory name is the filename with the basename removed. If a name
does not have a directory part, the directory is “.”
For example, the expression $(dirname dir1\dir2\a.out /etc/modules.conf /foo.ml bar.ml) evaluates to
dir1/dir2 /etc / ..
Note: this function is different from the dirof function.
The function dirname is simple a function over strings, while
dirof is a function on filenames.
$(rootname files) : String Sequence
files : String Sequence
The rootname function returns the root name for a list of files.
The rootname is the filename with the final suffix removed.
For example, the expression $(rootname dir1/dir2/a.out /etc/a.b.c /foo.ml) evaluates to
dir1/dir2/a /etc/a.b /foo.
$(dirof files) : Dir Sequence
files : File Sequence
$(tailof files) : String Sequence
files : File Sequence
The dirof function returns the directory for each of the listed files.
The tailof function returns the tail part (the lost part of the path).
For example, the expression $(dirof dir/dir2/a.out /etc/modules.conf /foo.ml) evaluates
to the directories dir1/dir2 /etc /, and $(dirof dir/dir2/a.out /etc/modules.conf /foo.ml)
evaluates to a.out modules.conf foo.ml.
$(fullname files) : String Sequence
files : File Sequence
The fullname function returns the pathname relative to the project root
for each of the files or directories.
$(absname files) : String Sequence
files : File Sequence
The absname function returns the absolute pathname for each of the files
or directories.
$(homename files) : String Sequence
files : File Sequence
The homename function returns the name of a file in
tilde form, if possible. The unexpanded forms are computed
lazily: the homename function will usually evaluate to an absolute
pathname until the first tilde-expansion for the same directory.
$(suffix files) : String Sequence
files : StringSequence
The suffix function returns the suffixes for a list of files.
If a file has no suffix, the function returns the empty string.
For example, the expression $(suffix dir1/dir2/a.out /etc/a /foo.ml) evaluates
to .out .ml.
$(which files) : File Sequence
files : String Sequence
The which function searches for executables in the
current command search path, and returns file values
for each of the commands. It is an error if a command is
not found.
The where function is similar to which, except it returns the list of
all the locations of the given executable (in the order in which the
corresponding directories appear in $PATH). In case a command is handled
internally by the Shell object, the first string in the output will
describe the command as a built-in function.
% where echo
echo is a Shell object method (a built-in function)
/bin/echo
rehash()
The rehash function resets all search paths.
$(exists-in-path files) : String
files : String Sequence
The exists-in-path function tests whether all executables
are present in the current search path.
$(digest files) : String Array
file : File Array
raises RuntimeException
$(digest-optional files) : String Array
file : File Array
The digest and digest-optional functions compute MD5 digests
of files. The digest function raises an exception if a file
does no exist. The digest-optional returns false if a
file does no exist. MD5 digests are cached.
$(find-in-path path, files) : File Array
path : Dir Array
files : String Array
raises RuntimeException
$(find-in-path-optional path, files) : File Array
The find-in-path function searches for the files in a search
path. Only the tail of the filename is significant. The find-in-path
function raises an exception if the file can't be found.
The find-in-path-optional function silently removes
files that can't be found.
$(digest-in-path path, files) : String/File Array
path : Dir Array
files : String Array
raises RuntimeException
$(digest-in-path-optional path, files) : String/File Array
The digest-in-path function searches for the files in a search
path and returns the file and digest for each file. Only the tail of the
filename is significant. The digest-in-path function raises an exception
if the file can't be found. The digest-in-path-optional
function silently removes elements that can't be found.
$(file-exists files) : String
$(target-exists files) : String
$(target-is-proper files) : String
files : File Sequence
The file-exists function checks whether the files listed exist.
The target-exists function is similar to the file-exists function.
However, it returns true if the file exists or if it can be built
by the current project. The target-is-proper returns true only
if the file can be generated in the current project.
$(stat-reset files) : String
files : File Sequence
OMake uses a stat-cache. The stat-reset function reset the stat
information for the given files, forcing the stat information to
be recomputed the next time it is requested.
$(filter-exists files) : File Sequence
$(filter-targets files) : File Sequence
$(filter-proper-targets) : File Sequence
files : File Sequence
The filter-exists, filter-targets, and filter-proper-targets
functions remove files from a list of files.
filter-exists: the result is the list of files that exist.
filter-targets: the result is the list of files either exist, or
can be built by the current project.
filter-proper-targets: the result is the list of files that can
be built in the current project.
One way to create a simple “distclean” rule that removes generated files from
the project is by removing all files that can be built in the current
project.
CAUTION: you should be careful before you do this. The rule removes any file that can potentially be reconstructed. There is no check to make sure that the commands to rebuild the file would actually succeed. Also, note that no file outside the current project will be deleted.
.PHONY: distclean
distclean:
rm $(filter-proper-targets $(ls R, .))
If you use CVS, you may wish to utilize the cvs_realclean program that
is distributed with OMake in order to create a “distclean” rule that would
delete all the files thare are not known to CVS. For example, if you already have a more traditional
“clean” target defined in your project, and if you want the “distclean” rule to
be interactive by default, you can write the following:
if $(not $(defined FORCE_REALCLEAN))
FORCE_REALCLEAN = false
export
distclean: clean
cvs_realclean $(if $(FORCE_REALCLEAN), -f) -i .omakedb -i .omakedb.lock
You can add more files that you want to always keep (such as configuration files) with the -i option.
Similarly, if you use Subversion, you utilize the build/svn_realclean.om script that comes with OMake:
if $(not $(defined FORCE_REALCLEAN))
FORCE_REALCLEAN = false
export
open build/svn_realclean
distclean: clean
svn_realclean $(if $(FORCE_REALCLEAN), -f) -i .omakedb -i .omakedb.lock
See also the dependencies-proper function for an alternate method for removing intermediate files.
$(find-targets-in-path path files) : File Array
$(find-targets-in-path-optional path, files) : File Array
path : Dir Array
files : File Sequence
The find-target-in-path function searches for targets in the
search path. For each file file in the file list, the path is
searched sequentially for a directory dir such that the target
dir/file exists. If so, the file dir/file is returned.
For example, suppose you are building a C project, and project
contains a subdirectory src/ containing only the files
fee.c and foo.c. The following expression
evaluates to the files src/fee.o src/foo.o even
if the files have not already been built.
$(find-targets-in-path lib src, fee.o foo.o)
# Evaluates to
src/fee.o src/foo.o
The find-targets-in-path
function raises an exception if the file can't be found.
The find-targets-in-path-optional function silently removes
targets that can't be found.
$(find-targets-in-path-optional lib src, fee.o foo.o fum.o)
# Evaluates to
src/fee.o src/foo.o
The find-ocaml-targets-in-path-optional function is very similar to the
find-targets-in-path-optional one, except an OCaml-style search
is used, where for every element of the search path and for every name being
searched for, first the uncapitalized version is tried and if it is not buildable,
then the capitalized version is tried next.
$(file-sort order, files) : File Sequence
order : String
files : File Sequence
The file-sort function sorts a list of filenames by
build order augmented by a set of sort rules. Sort
rules are declared using the .ORDER target.
The .BUILDORDER defines the default order.
$(file-sort <order>, <files>)
For example, suppose we have the following set of rules.
a: b c
b: d
c: d
.DEFAULT: a b c d
echo $(file-sort .BUILDORDER, a b c d)
In the case, the sorter produces the result d b c a.
That is, a target is sorted after its dependencies.
The sorter is frequently used to sort files that are to be linked
by their dependencies (for languages where this matters).
There are three important restrictions to the sorter:
It is possible to further constrain the sorter through the use of
sort rules. A sort rule is declared in two steps. The
target must be listed as an .ORDER target; and then
a set of sort rules must be given. A sort rule defines
a pattern constraint.
.ORDER: .MYORDER
.MYORDER: %.foo: %.bar
.MYORDER: %.bar: %.baz
.DEFAULT: a.foo b.bar c.baz d.baz
echo $(sort .MYORDER, a.foo b.bar c.baz d.baz)
In this example, the .MYORDER sort rule specifies that any
file with a suffix .foo should be placed after any file with
suffix .bar, and any file with suffix .bar should be
placed after a file with suffix .baz.
In this example, the result of the sort is d.baz c.baz b.bar a.foo.
file-check-sort(files)
files : File Sequence
raises RuntimeException
The file-check-sort function checks whether a list of files
is in sort order. If so, the list is returned unchanged.
If not, the function raises an exception.
$(file-check-sort <order>, <files>)
OMake commands are “glob-expanded” before being executed. That is, names may contain patterns that are expanded to sequences of file and directory names. The syntax follows the standard bash(1), csh(1), syntax, with the following rules.
/ or \ characters. For example, the following pathnames
refer to the same file: /home/jyh/OMakefile and /home\jyh/OMakefile.For the following examples, suppose that a directory /dir contains files
named a, -a, a.b, and b.c.
/dir/a* expands to /dir/a /dir/aa /dir/a.b./dir/?a expands
the filename /dir/-a.-, the - should occur as the first character in
the range.| Pattern | Expansion |
/dir/[a-b]* | /dir/a /dir/a.b /dir/b.c |
/dir/[-a-b]* | /dir/a /dir/-a /dir/a.b /dir/b.c |
/dir/[-a]* | /dir/a /dir/-a /dir/a.b |
| Pattern | Expansion |
a{b,c,d} | ab ac ad |
a{b{c,d},e} | abc abd ae |
a{?{[A-Z],d},*} | a?[A-Z] a?d a* |
| Pattern | Expansion |
~jyh | /home/jyh |
~bob/*.c | c:\Documents and Settings\users\bob |
\ character is both a pathname separator
and an escape character. If followed by a special glob character,
the \ changes the sense of the following character to non-special
status. Otherwise, \ is viewed as a pathname separator.| Pattern | Expansion |
~jyh/\* | ~jyh/* (* is literal) |
/dir/\[a-z? | /dir/[a-z? ([ is literal, ? is a pattern). |
c:\Program Files\[A-z] | c:\Program Files[A-z]* |
Note that the final case might be considered to be ambiguous (where \ should
be viewed as a pathname separator, not as an escape for the subsequent [
character. If you want to avoid this ambiguity on Win32, you should use the
forward slash / even for Win32 pathnames (the / is translated
to \ in the output).
| Pattern | Expansion |
c:/Program Files/[A-z]* | c:\Program Files\WindowsUpdate ... |
$(glob strings) : Node Array
strings : String Sequence
$(glob options, strings) : Node Array
options : String
strings : String Sequence
The glob function performs glob-expansion.
The . and .. entries are always ignored.
The options are:
\ character does not escape special characters.
In addition, the following variables may be defined that affect the
behavior of glob.
glob should ignore.
GLOB_ALLOW, it is ignored.
The returned files are sorted by name.
$(ls files) : Node Array
files : String Sequence
$(ls options, files) : Node Array
files : String Sequence
The ls function returns the filenames in a directory.
The . and .. entries are always ignored. The patterns are shell-style patterns, and are glob-expanded.
The options include all of the options to the glob function,
plus the following.
The GLOB_ALLOW and GLOB_IGNORE variables can be defined
to control the globbing behavior.
The returned files are sorted by name.
$(subdirs dirs) : Dir Array
dirs : String Sequence
$(subdirs options, dirs) : Dir Array
options : String
dirs : String Sequence
The subdirs function returns all the subdirectories
of a list of directories, recursively.
The possible options are the following:
mkdir(mode, node...)
mode : Int
node : Node
raises RuntimeException
mkdir(node...)
node : Node
raises RuntimeException
The mkdir function creates a directory, or a set of directories.
The following options are supported.
The Stat object represents an information about a filesystem node,
as returned by the stat and lstat functions.
It contains the following fields.
REG (regular file),
DIR (directory),
CHR (character device),
BLK (block device),
LNK (symbolic link),
FIFO (named pipe),
SOCK (socket).
Not all of the fields will have meaning on all operating systems.
$(stat node...) : Stat
node : Node or Channel
$(lstat node...) : Stat
node : Node or Channel
raises RuntimeException
The stat functions return file information.
If the file is a symbolic link, the stat function refers to the
destination of the link; the lstat function refers to the link
itself.
$(unlink file...)
file : File
#(rm file...)
file : File
$(rmdir dir...)
dir : Dir
raises RuntimeException
The unlink and rm functions remove a file.
The rmdir function removes a directory.
The following options are supported for rm and rmdir.
rename(old, new)
old : Node
new : Node
mv(nodes... dir)
nodes : Node Sequence
dir : Dir
cp(nodes... dir)
nodes : Node Sequence
dir : Dir
raises RuntimeException
The rename function changes the name of a file or directory named old
to new.
The mv function is similar, but if new is a directory, and it exists,
then the files specified by the sequence are moved into the directory. If not,
the behavior of mv is identical to rename. The cp function
is similar, but the original file is not removed.
The mv and cp functions take the following options.
link(src, dst)
src : Node
dst : Node
raises RuntimeException
The link function creates a hard link named dst to the file
or directory src.
Hard links may work under Win32 when NTFS is used.
Normally, only the superuser can create hard links to directories.
symlink(src, dst)
src : Node
dst : Node
raises RuntimeException
The symlink function creates a symbolic link dst that
points to the src file.
The link name is computed relative to
the target directory. For example, the expression
$(symlink a/b, c/d) creates a link named
c/d -> ../a/b.
Symbolic links are not supported in Win32. Consider using the ln-or-cp
Shell alias for cross-platform portable linking/copying.
$(readlink node...) : Node
node : Node
The readlink function reads the value of a symbolic link.
chmod(mode, dst...)
mode : Int
dst : Node or Channel
chmod(mode dst...)
mode : String
dst : Node Sequence
raises RuntimeException
The chmod function changes the permissions of the targets.
Options:
chown(uid, gid, node...)
uid : Int
gid : Int
node : Node or Channel
chown(uid, node...)
uid : Int
node : Node or Channel
raises RuntimeException
The chown function changes the user and group id of the file.
If the gid is not specified, it is not changed. If either
id is -1, that id is not changed.
truncate(length, node...)
length : Int
node : Node or Channel
raises RuntimeException
The truncate function truncates a file to the given length.
$(umask mode) : Int
mode : Int
raises RuntimeException
Sets the file mode creation mask. The previous mask is returned. This value is not scoped, changes have global effect.
vmount(src, dst)
src, dst : Dir
vmount(flags, src, dst)
flags : String
src, dst : Dir
“Mount” the src directory on the dst directory. This is
a virtual mount, changing the behavior of the $(file ...) function.
When the $(file str) function is used, the resulting file is taken
relative to the src directory if the file exists. Otherwise, the
file is relative to the current directory.
The main purpose of the vmount function is to support multiple
builds with separate configurations or architectures.
The options are as follows.
src directory.
src directory.
Mount operations are scoped.
add-project-directories(dirs)
dirs : Dir Array
Add the directories to the set of directories that omake considers to be part of the project. This is mainly used to avoid omake complaining that the current directory is not part of the project.
remove-project-directories(dirs)
dirs : Dir Array
Removed the directories from the set of directories that omake considers to be part
of the project. This is mainly used to cancel a .SUBDIRS from including
a directory if it is determined that the directory does not need to be compiled.
test(exp) : Bool
exp : String Sequence
The expression grammar is as follows:
! expression : expression is not true
-a expression2 : both expressions are true
-o expression2 : at least one expression is true
( expression ) : expression is true
The base expressions are:
-n string : The string has nonzero length
-z string : The string has zero length
= string : The strings are equal
!= string : The strings are not equal-eq int2 : The integers are equal
-ne int2 : The integers are not equal
-gt int2 : int1 is larger than int2
-ge int2 : int2 is not larger than int1
-lt int2 : int1 is smaller than int2
-le int2 : int1 is not larger than int2-ef file2 : On Unix, file1 and file2 have the
same device and inode number.
On Win32, file1 and file2 have the
same name.
-nt file2 : file1 is newer than file2
-ot file2 : file1 is older than file2-b file : The file is a block special file
-c file : The file is a character special file
-d file : The file is a directory
-e file : The file exists
-f file : The file is a normal file
-g file : The set-group-id bit is set on the file
-G file : The file's group is the current effective group
-h file : The file is a symbolic link (also -L)
-k file : The file's sticky bit is set
-L file : The file is a symbolic link (also -h)
-O file : The file's owner is the current effective user
-p file : The file is a named pipe
-r file : The file is readable
-s file : The file is empty
-S file : The file is a socket
-u file : The set-user-id bit is set on the file
-w file : The file is writable
-x file : The file is executable
A string is any sequence of characters; leading - characters are allowed.
An int is a string that can be interpreted as an integer. Unlike traditional
versions of the test program, the leading characters may specify an arity. The
prefix 0b means the numbers is in binary; the prefix 0o means
the number is in octal; the prefix 0x means the number is in hexadecimal.
An int can also be specified as -l string, which evaluates to the length of
the string.
A file is a string that represents the name of a file.
The syntax mirrors that of the test(1) program. If you are on a Unix system, the man page explains more. Here are some examples.
# Create an empty file
osh> touch foo
# Is the file empty?
osh> test(-e foo)
- : true
osh> test(! -e foo)
- : false
# Create another file
osh> touch boo
# Is the newer file newer?
osh> test(boo -nt foo)
- : true
# A more complex query
# boo is newer than foo, and foo is empty
osh> test(\( boo -nt foo \) -a -e foo)
- : true
find(exp) : Node Array
exp : String Sequence
The find function searches a directory recursively, returning the
files for which the expression evaluates to true.
The expression argument uses the same syntax as the test function,
with the following exceptions.
{} string expands to the current file being examined.
The syntax of the expression is the same as test, with the following
additions.
-name string : The current file matches the glob expression
(see Section 11.4).
The find function performs a recursive scan of all subdirectories.
The following call is being run from the root of the omake source directory.
osh> find(. -name fo* )
- : <array
/home/jyh/.../omake/mk/.svn/format
/home/jyh/.../omake/RPM/.svn/format
...
/home/jyh/.../omake/osx_resources/installer_files/.svn/format>
Another example, listing only those files that are normal files or symbolic links.
osh> find(. -name fo* -a \( -f {} -o -L {} \))
- : <array
/home/jyh/.../omake/mk/.svn/format
/home/jyh/.../omake/RPM/.svn/format
...
/home/jyh/.../omake/osx_resources/installer_files/.svn/format>
The following variables define the standard channels.
stdin : InChannel
The standard input channel, open for reading.
stdout : OutChannel
The standard output channel, open for writing.
stderr : OutChannel
The standard error channel, open for writing.
The open-in-string treats a string as if it were a file
and returns a channel for reading.
$(open-in-string s) : Channel
s : String
The open-out-string creates a channel that writes to a
string instead of a file. The string may be retrieved with the
out-contents function.
$(open-out-string) : Channel
$(out-contents chan) : String
chan : OutChannel
The fopen function opens a file for reading or writing.
$(fopen file, mode) : Channel
file : File
mode : String
The file is the name of the file to be opened.
The mode is a combination of the following characters.
Binary mode is not significant on Unix systems, where text and binary modes are equivalent.
$(close channel...)
channel : Channel
The close function closes a file that was previously opened
with fopen.
$(read channel, amount) : String
channel : InChannel
amount : Int
raises RuntimeException
The read function reads up to amount
bytes from an input channel, and returns
the data that was read. If an end-of-file condition is reached,
the function raises a RuntimeException exception.
$(write channel, buffer, offset, amount) : String
channel : OutChannel
buffer : String
offset : Int
amount : Int
$(write channel, buffer) : String
channel : OutChannel
buffer : String
raises RuntimeException
In the 4-argument form, the write function writes
bytes to the output channel channel from the buffer,
starting at position offset. Up to amount bytes
are written. The function returns the number of bytes that were
written.
The 3-argument form is similar, but the offset is 0.
In the 2-argument form, the offset is 0, and the amount
if the length of the buffer.
If an end-of-file condition is reached,
the function raises a RuntimeException exception.
$(lseek channel, offset, whence) : Int
channel : Channel
offset : Int
whence : String
raises RuntimeException
The lseek function repositions the offset of the
channel channel according to the whence directive, as
follows:
offset.
offset bytes.
offset bytes.
The lseek function returns the new position in the file.
rewind(channel...)
channel : Channel
The rewind function set the current file position to the
beginning of the file.
$(tell channel...) : Int...
channel : Channel
raises RuntimeException
The tell function returns the current position of the channel.
$(flush channel...)
channel : OutChannel
The flush function can be used only on files that are open for writing.
It flushes all pending data to the file.
$(dup channel) : Channel
channel : Channel
raises RuntimeException
The dup function returns a new channel referencing the
same file as the argument.
dup2(channel1, channel2)
channel1 : Channel
channel2 : Channel
raises RuntimeException
The dup2 function causes channel2 to refer to the same
file as channel1.
set-nonblock-mode(mode, channel...)
channel : Channel
mode : String
The set-nonblock-mode function sets the nonblocking flag on the
given channel. When IO is performed on the channel, and the operation
cannot be completed immediately, the operations raises a RuntimeException.
set-close-on-exec-mode(mode, channel...)
channel : Channel
mode : String
raises RuntimeException
The set-close-on-exec-mode function sets the close-on-exec
flags for the given channels. If the close-on-exec flag is set, the channel
is not inherited by child processes. Otherwise it is.
$(pipe) : Pipe raises RuntimeException
The pipe function creates a Pipe object, which has two
fields. The read field is a channel that is opened for
reading, and the write field is a channel that is opened
for writing.
mkfifo(mode, node...)
mode : Int
node : Node
The mkfifo function creates a named pipe.
$(select rfd..., wfd..., wfd..., timeout) : Select
rfd : InChannel
wfd : OutChannel
efd : Channel
timeout : float
raises RuntimeException
The select function polls for possible IO on a set of channels.
The rfd are a sequence of channels for reading, wfd are a
sequence of channels for writing, and efd are a sequence of
channels to poll for error conditions. The timeout specifies
the maximum amount of time to wait for events.
On successful return, select returns a Select object,
which has the following fields:
lockf(channel, command, len)
channel : Channel
command : String
len : Int
raises RuntimeException
The lockf function places a lock on a region of the channel.
The region starts at the current position and extends for len
bytes.
The possible values for command are the following.
The InetAddr object describes an Internet address.
It contains the following fields.
String: the Internet address.
Int: the port number.
A Host object contains the following fields.
String: the name of the host.
String Array: other names by which the host is known.
String: the preferred socket domain.
InetAddr Array: an array of Internet addresses belonging to the host.
$(gethostbyname host...) : Host...
host : String
raises RuntimeException
The gethostbyname function returns a Host object
for the specified host. The host may specify a domain name
or an Internet address.
The Protocol object represents a protocol entry.
It has the following fields.
String: the canonical name of the protocol.
String Array: aliases for the protocol.
Int: the protocol number.
$(getprotobyname name...) : Protocol...
name : Int or String
raises RuntimeException
The getprotobyname function returns a Protocol object for the
specified protocol. The name may be a protocol name, or a
protocol number.
The Service object represents a network service.
It has the following fields.
String: the name of the service.
String Array: aliases for the service.
Int: the port number of the service.
Protocol: the protocol for the service.
$(getservbyname service...) : Service...
service : String or Int
raises RuntimeException
The getservbyname function gets the information for a network service.
The service may be specified as a service name or number.
$(socket domain, type, protocol) : Channel
domain : String
type : String
protocol : String
raises RuntimeException
The socket function creates an unbound socket.
The possible values for the arguments are as follows.
The domain may have the following values.
The type may have the following values.
The protocol is an Int or String that specifies
a protocol in the protocols database.
bind(socket, host, port)
socket : InOutChannel
host : String
port : Int
bind(socket, file)
socket : InOutChannel
file : File
raise RuntimeException
The bind function binds a socket to an address.
The 3-argument form specifies an Internet connection, the host specifies a host name
or IP address, and the port is a port number.
The 2-argument form is for Unix sockets. The file specifies the filename
for the address.
listen(socket, requests)
socket : InOutChannel
requests : Int
raises RuntimeException
The listen function sets up the socket for receiving up to requests number
of pending connection requests.
$(accept socket) : InOutChannel
socket : InOutChannel
raises RuntimeException
The accept function accepts a connection on a socket.
connect(socket, addr, port)
socket : InOutChannel
addr : String
port : int
connect(socket, name)
socket : InOutChannel
name : File
raise RuntimeException
The connect function connects a socket to a remote address.
The 3-argument form specifies an Internet connection.
The addr argument is the Internet address of the remote host,
specified as a domain name or IP address. The port argument
is the port number.
The 2-argument form is for Unix sockets. The name argument
is the filename of the socket.
$(getc) : String
$(getc file) : String
file : InChannel or File
raises RuntimeException
The getc function returns the next character of a file.
If the argument is not specified, stdin is used as input.
If the end of file has been reached, the function returns false.
$(gets) : String
$(gets channel) : String
channel : InChannel or File
raises RuntimeException
The gets function returns the next line from a file.
The function returns the empty string if the end of file has been reached.
The line terminator is removed.
$(fgets) : String
$(fgets channel) : String
channel : InChannel or File
raises RuntimeException
The fgets function returns the next line from a file that has been
opened for reading with fopen. The function returns the empty string
if the end of file has been reached. The returned string is returned as
literal data. The line terminator is not removed.
Output is printed with the print and println functions.
The println function adds a terminating newline to the value being
printed, the print function does not.
fprint(<file>, <string>)
print(<string>)
eprint(<string>)
fprintln(<file>, <string>)
println(<string>)
eprintln(<string>)
The fprint functions print to a file that has been previously opened with
fopen. The print functions print to the standard output channel, and
the eprint functions print to the standard error channel.
Values can be printed with the printv and printvln functions.
The printvln function adds a terminating newline to the value being
printed, the printv function does not.
fprintv(<file>, <string>)
printv(<string>)
eprintv(<string>)
fprintvln(<file>, <string>)
printvln(<string>)
eprintvln(<string>)
The fprintv functions print to a file that has been previously opened with
fopen. The printv functions print to the standard output channel, and
the eprintv functions print to the standard error channel.
set-channel-line(channel, filename, line)
channel : Channel
filename : File
line : int
Set the line number information for the channel.
Many of the higher-level functions use regular expressions. Regular expressions are defined by strings with syntax nearly identical to awk(1).
Strings may contain the following character constants.
\\ : a literal backslash.
\a : the alert character ^G.
\b : the backspace character ^H.
\f : the formfeed character ^L.
\n : the newline character ^J.
\r : the carriage return character ^M.
\t : the tab character ^I.
\v : the vertical tab character.
\xhh... : the character represented by the string
of hexadecimal digits h. All valid hexadecimal digits
following the sequence are considered to be part of the sequence.
\ddd : the character represented by 1, 2, or 3 octal
digits.
Regular expressions are defined using the special characters .\^$[(){}*?+.
c : matches the literal character c if c is not
a special character.
\c : matches the literal character c, even if c
is a special character.
. : matches any character, including newline.
^ : matches the beginning of a line.
$ : matches the end of line.
[abc...] : matches any of the characters abc...
[^abc...] : matches any character except abc...
r1|r2 : matches either r1 or r2.
r1r2 : matches r1 and then r2.
r+ : matches one or more occurrences of r.
r* : matches zero or more occurrences of r.
r? : matches zero or one occurrence of r.
(r) : parentheses are used for grouping; matches r.
\(r\) : also defines grouping, but the expression matched
within the parentheses is available to the output processor
through one of the variables $1, $2, ...
r{n} : matches exactly n occurrences of r.
r{n,} : matches n or more occurrences of r.
r{n,m} : matches at least n occurrences of r,
and no more than m occurrences.
\y: matches the empty string at either the beginning or
end of a word.
\B: matches the empty string within a word.
\<: matches the empty string at the beginning of a word.
\>: matches the empty string at the end of a word.
\w: matches any character in a word.
\W: matches any character that does not occur within a word.
\`: matches the empty string at the beginning of a file.
\': matches the empty string at the end of a file.
Character classes can be used to specify character sequences abstractly. Some of these sequences can change depending on your LOCALE.
[:alnum:] Alphanumeric characters.
[:alpha:] Alphabetic characters.
[:lower:] Lowercase alphabetic characters.
[:upper:] Uppercase alphabetic characters.
[:cntrl:] Control characters.
[:digit:] Numeric characters.
[:xdigit:] Numeric and hexadecimal characters.
[:graph:] Characters that are printable and visible.
[:print:] Characters that are printable, whether they are visible or not.
[:punct:] Punctuation characters.
[:blank:] Space or tab characters.
[:space:] Whitespace characters.
cat(files) : Sequence
files : File or InChannel Sequence
The cat function concatenates the output from multiple files
and returns it as a string.
grep(pattern) : String # input from stdin, default options
pattern : String
grep(pattern, files) : String # default options
pattern : String
files : File Sequence
grep(options, pattern, files) : String
options : String
pattern : String
files : File Sequence
The grep function searches for occurrences of a regular
expression pattern in a set of files, and prints lines that match.
This is like a highly-simplified version of grep(1).
The options are:
grep is not displayed.
The pattern is a regular expression.
If successful (grep found a match), the function returns true.
Otherwise, it returns false.
scan(input-files)
case string1
body1
case string2
body2
...
default
bodyd
The scan function provides input processing in command-line form.
The function takes file/filename arguments. If called with no
arguments, the input is taken from stdin. If arguments are provided,
each specifies an InChannel, or the name of a file for input.
Output is always to stdout.
The scan function operates by reading the input one line at a time,
and processing it according to the following algorithm.
For each line,
the record is first split into fields, and
the fields are bound to the variables $1, $2, .... The variable
$0 is defined to be the entire line, and $* is an array
of all the field values. The $(NF) variable is defined to be the number
of fields.
Next, a case expression is selected. If string_i matches the token $1,
then body_i is evaluated. If the body ends in an export, the state
is passed to the next clause. Otherwise the value is discarded.
For example, here is an scan function that acts as a simple command processor.
calc() =
i = 0
scan(script.in)
case print
println($i)
case inc
i = $(add $i, 1)
export
case dec
i = $(sub $i, 1)
export
case addconst
i = $(add $i, $2)
export
default
eprintln($"Unknown command: $1")
The scan function also supports several options.
scan(options, files)
...
ls”, “-l”, “Program Files”.ls -l "Program Files"
Note, if you want to redirect the output to a file, the easiest way is to
redefine the stdout variable. The stdout variable is scoped the
same way as other variables, so this definition does not affect the meaning of
stdout outside the calc function.
calc() =
stdout = $(fopen script.out, w)
scan(script.in)
...
close(stdout)
awk(input-files)
case pattern1:
body1
case pattern2:
body2
...
default:
bodyd
or
awk(options, input-files)
case pattern1:
body1
case pattern2:
body2
...
default:
bodyd
The awk function provides input processing similar to awk(1),
but more limited. The input-files argument is a sequence of values,
each specifies an InChannel, or the name of a file for input.
If called with no options and no file arguments, the input is taken from stdin.
Output is always to stdout.
The variables RS and FS define record and field separators
as regular expressions.
The default value of RS is the regular expression \r|\n|\r\n.
The default value of FS is the regular expression [ \t]+.
The awk function operates by reading the input one record at a time,
and processing it according to the following algorithm.
For each line,
the record is first split into fields using the field separator FS, and
the fields are bound to the variables $1, $2, .... The variable
$0 is defined to be the entire line, and $* is an array
of all the field values. The $(NF) variable is defined to be the number
of fields.
Next, the cases are evaluated in order.
For each case, if the regular expression pattern_i matches the record $0,
then body_i is evaluated. If the body ends in an export, the state
is passed to the next clause. Otherwise the value is discarded. If the regular
expression contains \(r\) expression, those expression override the
fields $1, $2, ....
For example, here is an awk function to print the text between two
delimiters \begin{<name>} and \end{<name>}, where the <name>
must belong to a set passed as an argument to the filter function.
filter(names) =
print = false
awk(Awk.in)
case $"^\\end\{\([:alpha:]+\)\}"
if $(mem $1, $(names))
print = false
export
export
default
if $(print)
println($0)
case $"^\\begin\{\([:alpha:]+\)\}"
print = $(mem $1, $(names))
export
Note, if you want to redirect the output to a file, the easiest way is to
redefine the stdout variable. The stdout variable is scoped the
same way as other variables, so this definition does not affect the meaning of
stdout outside the filter function.
filter(names) =
stdout = $(fopen file.out, w)
awk(Awk.in)
...
close(stdout)
Options.
The break function can be used to abort the loop,
exiting the awk function immediately.
fsubst(files)
case pattern1 [options]
body1
case pattern2 [options]
body2
...
default
bodyd
The fsubst function provides a sed(1)-like substitution
function. Similar to awk, if fsubst is called with no
arguments, the input is taken from stdin. If arguments are provided,
each specifies an InChannel, or the name of a file for input.
The RS variable defines a regular expression that determines a record separator,
The default value of RS is the regular expression \r|\n|\r\n.
The fsubst function reads the file one record at a time.
For each record, the cases are evaluated in order. Each case defines
a substitution from a substring matching the pattern to
replacement text defined by the body.
Currently, there is only one option: g.
If specified, each clause specifies a global replacement,
and all instances of the pattern define a substitution.
Otherwise, the substitution is applied only once.
Output can be redirected by redefining the stdout variable.
For example, the following program replaces all occurrences of
an expression word. with its capitalized form.
section
stdout = $(fopen Subst.out, w)
fsubst(Subst.in)
case $"\<\([[:alnum:]]+\)\." g
value $(capitalize $1).
close(stdout)
lex(files)
case pattern1
body1
case pattern2
body2
...
default
bodyd
The lex function provides a simple lexical-style scanner
function. The input is a sequence of files or channels. The cases
specify regular expressions. Each time the input is read, the regular
expression that matches the longest prefix of the input is selected,
and the body is evaluated.
If two clauses both match the same input, the last one is selected
for execution. The default case matches the regular expression .;
you probably want to place it first in the pattern list.
If the body end with an export directive,
the state is passed to the next clause.
For example, the following program collects all occurrences of alphanumeric words in an input file.
collect-words($(files)) =
words[] =
lex($(files))
default
# empty
case $"[[:alnum:]]+" g
words[] += $0
export
The default case, if one exists, matches single characters. Since
It is an error if the input does not match any of the regular expressions.
The break function can be used to abort the loop.
lex-search(files)
case pattern1
body1
case pattern2
body2
...
default
bodyd
The lex-search function is like the lex function, but input that
does not match any of the regular expressions is skipped. If the clauses include
a default case, then the default matches any skipped text.
For example, the following program collects all occurrences of alphanumeric words in an input file, skipping any other text.
collect-words($(files)) =
words[] =
lex-search($(files))
default
eprintln(Skipped $0)
case $"[[:alnum:]]+" g
words[] += $0
export
The default case, if one exists, matches single characters. Since
It is an error if the input does not match any of the regular expressions.
The break function can be used to abort the loop.
The Lexer object defines a facility for lexical analysis, similar to the
lex(1) and flex(1) programs.
In omake, lexical analyzers can be constructed dynamically by extending
the Lexer class. A lexer definition consists of a set of directives specified
with method calls, and set of clauses specified as rules.
For example, consider the following lexer definition, which is intended for lexical analysis of simple arithmetic expressions for a desktop calculator.
lexer1. =
extends $(Lexer)
other: .
eprintln(Illegal character: $* )
lex()
white: $"[[:space:]]+"
lex()
op: $"[-+*/()]"
switch $*
case +
Token.unit($(loc), plus)
case -
Token.unit($(loc), minus)
case *
Token.unit($(loc), mul)
case /
Token.unit($(loc), div)
case $"("
Token.unit($(loc), lparen)
case $")"
Token.unit($(loc), rparen)
number: $"[[:digit:]]+"
Token.pair($(loc), exp, $(int $* ))
eof: $"\'"
Token.unit($(loc), eof)
This program defines an object lexer1 the extends the Lexer
object, which defines lexing environment.
The remainder of the definition consists of a set of clauses, each with a method name before the colon; a regular expression after the colon; and in this case, a body. The body is optional, if it is not specified, the method with the given name should already exist in the lexer definition.
NB The clause that matches the longest prefix of the input is selected. If two clauses match the same input prefix, then the last one is selected. This is unlike most standard lexers, but makes more sense for extensible grammars.
The first clause matches any input that is not matched by the other clauses. In this case, an error message is printed for any unknown character, and the input is skipped. Note that this clause is selected only if no other clause matches.
The second clause is responsible for ignoring white space. If whitespace is found, it is ignored, and the lexer is called recursively.
The third clause is responsible for the arithmetic operators.
It makes use of the Token object, which defines three
fields: a loc field that represents the source location;
a name; and a value.
The lexer defines the loc variable to be the location
of the current lexeme in each of the method bodies, so we can use
that value to create the tokens.
The Token.unit($(loc), name)
method constructs a new Token object with the given name,
and a default value.
The number clause matches nonnegative integer constants.
The Token.pair($(loc), name, value) constructs a token with the
given name and value.
Lexer object operate on InChannel objects.
The method lexer1.lex-channel(channel) reads the next
token from the channel argument.
During lexical analysis, clauses are selected by longest match.
That is, the clause that matches the longest sequence of input
characters is chosen for evaluation. If no clause matches, the
lexer raises a RuntimeException. If more than one clause
matches the same amount of input, the first one is chosen
for evaluation.
Suppose we wish to augment the lexer example so that it ignores
comments. We will define comments as any text that begins with
the string (*, ends with *), and comments may
be nested.
One convenient way to do this is to define a separate lexer just to skip comments.
lex-comment. =
extends $(Lexer)
level = 0
other: .
lex()
term: $"[*][)]"
if $(not $(eq $(level), 0))
level = $(sub $(level), 1)
lex()
next: $"[(][*]"
level = $(add $(level), 1)
lex()
eof: $"\'"
eprintln(Unterminated comment)
This lexer contains a field level that keeps track of the nesting
level. On encountering a (* string, it increments the level,
and for *), it decrements the level if nonzero, and continues.
Next, we need to modify our previous lexer to skip comments.
We can do this by extending the lexer object lexer1
that we just created.
lexer1. +=
comment: $"[(][*]"
lex-comment.lex-channel($(channel))
lex()
The body for the comment clause calls the lex-comment lexer when
a comment is encountered, and continues lexing when that lexer returns.
Clause bodies may also end with an export directive. In this case
the lexer object itself is used as the returned token. If used with
the Parser object below, the lexer should define the loc, name
and value fields in each export clause. Each time
the Parser calls the lexer, it calls it with the lexer returned
from the previous lex invocation.
The Parser object provides a facility for syntactic analysis based
on context-free grammars.
Parser objects are specified as a sequence of directives,
specified with method calls; and productions, specified as rules.
For example, let's finish building the desktop calculator started
in the Lexer example.
parser1. =
extends $(Parser)
#
# Use the main lexer
#
lexer = $(lexer1)
#
# Precedences, in ascending order
#
left(plus minus)
left(mul div)
right(uminus)
#
# A program
#
start(prog)
prog: exp eof
return $1
#
# Simple arithmetic expressions
#
exp: minus exp :prec: uminus
neg($2)
exp: exp plus exp
add($1, $3)
exp: exp minus exp
sub($1, $3)
exp: exp mul exp
mul($1, $3)
exp: exp div exp
div($1, $3)
exp: lparen exp rparen
return $2
Parsers are defined as extensions of the Parser class.
A Parser object must have a lexer field. The lexer
is not required to be a Lexer object, but it must provide
a lexer.lex() method that returns a token object with
name and value fields. For this example, we use the
lexer1 object that we defined previously.
The next step is to define precedences for the terminal symbols.
The precedences are defined with the left, right,
and nonassoc methods in order of increasing precedence.
The grammar must have at least one start symbol, declared with
the start method.
Next, the productions in the grammar are listed as rules. The name of the production is listed before the colon, and a sequence of variables is listed to the right of the colon. The body is a semantic action to be evaluated when the production is recognized as part of the input.
In this example, these are the productions for the arithmetic
expressions recognized by the desktop calculator. The semantic
action performs the calculation. The variables $1, $2, ...
correspond to the values associated with each of the variables
on the right-hand-side of the production.
The parser is called with the $(parser1.parse-channel start, channel)
or $(parser1.parse-file start, file) functions. The start
argument is the start symbol, and the channel or file
is the input to the parser.
The parser generator generates a pushdown automation based on LALR(1) tables. As usual, if the grammar is ambiguous, this may generate shift/reduce or reduce/reduce conflicts. These conflicts are printed to standard output when the automaton is generated.
By default, the automaton is not constructed until the parser is first used.
The build(debug) method forces the construction of the automaton.
While not required, it is wise to finish each complete parser with
a call to the build(debug) method. If the debug variable
is set, this also prints with parser table together with any conflicts.
The loc variable is defined within action bodies, and represents
the input range for all tokens on the right-hand-side of the production.
Parsers may also be extended by inheritance.
For example, let's extend the grammar so that it also recognizes
the << and >> shift operations.
First, we extend the lexer so that it recognizes these tokens.
This time, we choose to leave lexer1 intact, instead of
using the += operator.
lexer2. =
extends $(lexer1)
lsl: $"<<"
Token.unit($(loc), lsl)
asr: $">>"
Token.unit($(loc), asr)
Next, we extend the parser to handle these new operators.
We intend that the bitwise operators have lower precedence
than the other arithmetic operators. The two-argument form
of the left method accomplishes this.
parser2. =
extends $(parser1)
left(plus, lsl lsr asr)
lexer = $(lexer2)
exp: exp lsl exp
lsl($1, $3)
exp: exp asr exp
asr($1, $3)
In this case, we use the new lexer lexer2, and we add productions
for the new shift operations.
The Passwd object represents an entry in the system's user database.
It contains the following fields.
pw_name: the login name.
pw_passwd: the encrypted password.
pw_uid: user id of the user.
pw_gid: group id of the user.
pw_gecos: the user name or comment field.
pw_dir: the user's home directory.
pw_shell: the user's default shell.
Not all the fields will have meaning on all operating systems.
$(getpwnam name...) : Passwd
name : String
$(getpwuid uid...) : Passwd
uid : Int
raises RuntimeException
The getpwnam function looks up an entry by the user's login and the getpwuid
function looks up an entry by user's numerical id (uid). If no entry is found, an exception
will be raised.
$(getpwents) : Array
The getpwents function returns an array of Passwd objects, one for every user
fund in the system user database. Note that depending on the operating system and on the setup
of the user database, the returned array may be incomplete or even empty.
The Group object represents an entry in the system's user group database.
It contains the following fields.
gr_name: the group name.
gr_group: the encrypted password.
gr_gid: group id of the group.
gr_mem: the group member's user names.
Not all the fields will have meaning on all operating systems.
$(getgrnam name...) : Group
name : String
$(getgrgid gid...) : Group
gid : Int
raises RuntimeException
The getgrnam function looks up a group entry by the group's name and the getgrgid
function looks up an entry by groups's numerical id (gid). If no entry is found, an exception
will be raised.
$(tgetstr id) : String
id : String
The tgetstr function looks up the terminal capability with the indicated id.
This assumes the terminfo to lookup is given in the TERM environment variable. This
function returns an empty value if the given terminal capability is not defined.
Note: if you intend to use the value returned by tgetstr inside the shell
prompt, you need to wrap it using the prompt-invisible function.
$(xterm-escape-begin) : String $(xterm-escape-end) : String
The xterm-escape-begin and xterm-escape-end functions return the escape sequences
that can be used to set the XTerm window title. Will return empty values if this capability is
not available.
Note: if you intend to use these strings inside the shell prompt, you need to use
$(prompt_invisible_begin)$(xterm-escape-begin) and
$(xterm-escape-end)$(prompt_invisible_end).
$(xterm-escape s) : Sequence
When the TERM environment variable indicates that the XTerm title setting capability is available,
$(xterm-escape s) is equivalent to $(xterm-escape-begin)s$(xterm-escape-end). Otherwise, it
returns an empty value.
Note: if you intend to use the value returned by xterm-escape inside the shell
prompt, you need to wrap it using the prompt-invisible function.
$(prompt-invisible-begin) : String $(prompt-invisible-end) : String
The prompt-invisible-begin and prompt-invisible-end functions return the escape sequences
that must used to mark the “invisible” sections of the shell prompt (such as various escape sequences).
$(prompt-invisible s) : Sequence
The prompt-invisible will wrap its argument with $(prompt-invisible-begin) and
$(prompt-invisible-end). All the `invisible” sections of the shell prompt (such as various
escape sequences) must be wrapped this way.
$(gettimeofday) : Float
The gettimeofday function returns the time of day in seconds
since January 1, 1970.
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