srfi.170 - POSIX API ¶This module provides a portable interface to a part of POSIX API, mainly filesystem interface.
In Gauche, it is a thin wrapper of Gauche’s native system interface (see System interface). You may want to use this module for a portable code.
[SRFI-170]{srfi.170}
Returns #t iff obj is a condition thrown due to
underlying POSIX-layer error. On Gauche, POSIX-layer condition
is the same as <system-error> (see Conditions).
[SRFI-170]{srfi.170}
The argument must be a POSIX-layer condition, that is,
an object that satisfies posix-error?. In Gauche,
it is a <system-error> object.
Returns the POSIX error name (symbol)
of the given condition, such as ENOENT.
See also sys-errno->symbol (see System inquiry).
[SRFI-170]{srfi.170}
The argument must be a POSIX-layer condition, that is,
an object that satisfies posix-error?. In Gauche,
it is a <system-error> object.
Returns the error message (string) describing the error,
e.g. "No such file or directory".
See also sys-strerror (see System inquiry).
[SRFI-170]{srfi.170}
Opens a file named by fname and returns a port to read or write
the file. You have finer control than
open-input-file/open-output-file.
The port-type argument must be either one of the value
of the constant binary-input, textual-input,
binary-output, textual-output and
binary-input/output. The direction of the returned port
is determined by this argument.
Gauche doesn’t distinguish textual ports and binary ports.
The flags argument is a bitwise ior of
zero or more of the following bitmasks:
open/append, open/create, open/exclusive,
open/nofollow and open/truncate. These corresponds
to the POSIX flags O_APPEND, O_CREAT, O_EXCL,
O_NOFOLLOW and O_TRUNC. Gauche exposes the POSIX flags
in gauche.fcntl (see gauche.fcntl - Low-level file operations).
Note: POSIX open(2) also requires one of the bitmasks
O_RDONLY, O_WRONLY and O_RDWR. These flags
are deduced from the port-type argument.
The optional permission is an integer permission bits
to be used when a new file is created. The actual permission bits
are also affected by the current umask.
The optional buffer-mode is a value of either one of the followings:
buffer-none, buffer-block, and buffer-line.
[SRFI-170]{srfi.170}
Creates a Scheme port wrapping an integer file descriptor fd.
The descriptor shouldn’t be used by other Scheme ports. After calling
this procedure, no I/O should be done via fd directly; the descriptor
is “owned” by the port, and will be closed once the port is closed.
The port-type argument must be either one of the value
of the constant binary-input, textual-input,
binary-output, textual-output and
binary-input/output. The direction must match how fd was
opened.
The optional buffer-mode is a value of either one of the followings:
buffer-none, buffer-block, and buffer-line.
[SRFI-170]{srfi.170}
Constants to be used as port-type argument of
open-file and fd->port.
[SRFI-170]{srfi.170}
Constants to be used as buffer-mode argument of
open-file and fd->port.
[SRFI-170]{srfi.170}
Bitmask constants to be used as flags argument of
open-file.
[SRFI-170]{srfi.170}
Corresponds to Gauche’s built-in sys-mkdir, sys-mkfifo,
sys-link and sys-symlink.
The default value of permission is #o775 for
create-directory, and #o664 for create-fifo
(It’s not optoinal for Gauche’s built-in).
On Windows, create-fifo and create-symlink are
not supported. Procedures exist, but raise an error when called.
[SRFI-170]{srfi.170}
Gauche’s sys-readlink.
[SRFI-170]{srfi.170}
Gauche’s sys-rename.
[SRFI-170]{srfi.170}
Gauche’s sys-rmdir. The directory must be empty.
To remove directory that may not be empty,
you can use delete-directory*
in file.util (see Directory utilities).
[SRFI-170]{srfi.170}
Gauche’s sys-chown. The uid and gid arguments
should be an integer uid/gid, or the value of the constant
owner/unchanged and group/unchanged, respectively,
to indicate to keep the original value.
[SRFI-170]{srfi.170}
Constants to be passed as uid and gid arguments
of set-file-owner, respectively.
[SRFI-170]{srfi.170}
Gauche’s sys-utime. The atime and mtime
arguments must be a <time> object (see Time), or
either one of the values of constants time/now or
time/unchanged. The constant time/now
indicates the time when the procedure is called,
and the constant time/unchanged indicates the
corresponding timestamp remains the same.
[SRFI-170]{srfi.170}
Constants that can be passed to atime and mtime
arguments of set-file-times.
[SRFI-170]{srfi.170}
The first argument can be a string filename or a open port associated
to a file. If it is a filename, sys-truncate is called,
and if it is a port, sys-ftruncate is called.
[SRFI-170]{srfi.170}
Gauche’s sys-stat, sys-lstat or sys-fstat.
The first argument can be a string filename or a open port associated
to a file. If it is a filename, sys-stat or sys-lstat
is called depending on whether follow? is #t or #f.
If it is a port, sys-fstat is called.
Returns a file-info object, which is a <sys-stat> instance
in Gauche (see File stats).
[SRFI-170]{srfi.170}
Returns #t iff obj is a file-info object, which is
a <sys-stat> instance in Gauche (see File stats).
[SRFI-170]{srfi.170}
Accessorso of file-info object (<sys-stat>) (see File stats).
Access its dev, ino, mode, nlink,
uid, gid, rdev, size,
blksize, blocks, atim, mtim, ctim
slots, respectively.
Note: <sys-stat>’s atime, mtime and ctime
contains integer for the backward compatibility, while
file-info:atime, file-info:mtime and file-info:ctime
returns <time> object.
[SRFI-170]{srfi.170}
Returns true iff the file-info object (<sys-stat> is of the
respective type. (file-info-device? returns true if
the file is either block or character device).
It corresponds to the type slot of <sys-stat>.
[SRFI-170]{srfi.170}
Gauche’s sys-chmod.
[SRFI-170]{srfi.170}
Returns a list of filenames in the directory named dir.
Similar to directory-list in file.util
(see Directory utilities), but (1) it never includes
. and .. (as true value is given to :children?
argument of directory-list), and (2) it doesn’t include
files beginning with . by default, unless dotfiles? is true.
[SRFI-170]{srfi.170}
Returns a generator (see gauche.generator - Generators) that generates file names
in the directory named dir. The names never include
. and .., and the filenames beginning with . is
omitted unless dotfiles? is true.
[SRFI-170]{srfi.170}
This is a directory scanner API more close to POSIX opendir,
readdir and closedir. A directory object is opened
with open-directory, and its entries (filenames) can be read
one by one using read-directory. If the file names are exausted,
read-directory returns an EOF object. A directory object
must be closed with close-directory.
The filenames to be retrieved are the same as directory-files; that is,
. and .. are never included, and names beginning with .
is exluded unless dotfiles? is true.
[SRFI-170]{srfi.170}
Gauche’s sys-realpath.
[SRFI-170]{srfi.170}
Returns the free space of a file system where a file specified by
path-or-port resides, in number of bytes.
[SRFI-170]{srfi.170}
A parameter holding a path prefix to be used by create-temp-file
and call-with-temporary-filename. In Gauche,
the default value is set to
(build-path (temporary-directory) (x->string (sys-getpid))).
See Temporary files and directories, for the description of
temporary-directory.
[SRFI-170]{srfi.170}
[SRFI-170]{srfi.170}
Note: For SRFI-170’s current-directory, we reuse
file.util’s one. See Directory utilities, for the description.
[SRFI-170]{srfi.170}
Returns the current umask value.
Gauche’s sys-umask without argument.
[SRFI-170]{srfi.170}
Sets mask, which must be a nonnegative exact integer,
as the current umask.
Gauche’s sys-umask, except that it returns unspecified value.
[SRFI-170]{srfi.170}
Sets the process’s current working directory to dir.
Gauche’s sys-chdir.
It can also be done with current-working-directory in file.util
(see Directory utilities).
[SRFI-170]{srfi.170}
Returns the current process id. Gauche’s sys-getpid.
[SRFI-170]{srfi.170}
Increments the current process’s nice value by delta, which must
be an exact integer. The lower the nice value is, the more chance
the process gets run. If omitted, delta is assumed to be 1.
Gauche’s sys-nice.
[SRFI-170]{srfi.170}
Gauche’s sys-getuid, sys-getgid, sys-geteuid,
sys-getegid, and sys-getgroups, respectievly.
[SRFI-170]{srfi.170}
Returns a user-info object, which is a <sys-passwd> instance
in Gauche, of a user specified by uid-or-name, which must be
an exact integer uid or a string username.
If it is an uid, sys-getpwuid is called, and if it is a username
sys-getpwnam is called.
[SRFI-170]{srfi.170}
Returns #t iff obj is a user-info object (<sys-passwd>).
[SRFI-170]{srfi.170}
Returns the value of name, uid, gid, dir,
shell and gecos slots of a user-info object (<sys-passwd)
uinfo.
[SRFI-170]{srfi.170}
[SRFI-170]{srfi.170}
Returns a group-info object, which is a <sys-group> instance
in Gauche, of a group specified by gid-or-name, which must be
an exact integer gid or a string groupname.
If it is an gid, sys-getgrgid is called, and if it is a groupname
sys-getgrnam is called.
[SRFI-170]{srfi.170}
Returns #t iff obj is a group-info object (<sys-group).
[SRFI-170]{srfi.170}
Returns the value of name and gid slot of a group info
(<sys-group>).
[SRFI-170]{srfi.170}
Same as current-time (see Time). Return value is a <time>
instance of time-utc.
[SRFI-170]{srfi.170}
Returns a <time> instance of time-monotonic, representing
a elapsed time since an unspecified epoch. It is guaranteed to monotonically
increasing during the lifetime of the process, even if the system clock
is modified.
See srfi.98 - Accessing environment variables, for getting environment variables.
This srfi defines the means to modify them.
[SRFI-170]{srfi.170}
Gauche’s sys-setenv with the third argument being #t
(overwrite the existing value).
[SRFI-170]{srfi.170}
Gauche’s sys-unsetenv.
[SRFI-170]{srfi.170}
Gauche’s sys-isatty.