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Module (chicken file)

This module provides various generic operations on files and directories. For more specific operations, see also Module (chicken file posix).

All errors related to failing file-operations will signal a condition of kind (exn i/o file).

Basic file operations

create-directory

create-directory NAME #!optional PARENTS?procedure

Creates a directory with the pathname NAME. If the PARENTS? argument is given and not false, any nonexistent parent directories are also created.

Notice that if NAME exists, create-directory won't try to create it and will return NAME (i.e., it won't raise an error when given a NAME that already exists).

copy-file

copy-file ORIGFILE NEWFILE #!optional CLOBBER BLOCKSIZEprocedure

Copies ORIGFILE (a string denoting some filename) to NEWFILE, BLOCKSIZE bytes at a time. BLOCKSIZE defaults to 1024, and must be a positive integer. Returns the number of bytes copied on success, or errors on failure. CLOBBER determines the behaviour of copy-file when NEWFILE is already extant. When set to #f (default), an error is signaled. When set to any other value, NEWFILE is overwritten. copy-file will work across filesystems and devices and is not platform-dependent.

move-file

move-file ORIGFILE NEWFILE #!optional CLOBBER BLOCKSIZEprocedure

Moves ORIGFILE (a string denoting some filename) to NEWFILE, with the same semantics as copy-file, above. move-file is safe across filesystems and devices (unlike rename-file). It is possible for an error to be signaled despite partial success if NEWFILE could be created and fully written but removing ORIGFILE fails.

If CLOBBER is given and not #f, NEWFILE will be replaced when it already exists, otherwise an error is signaled.

The BLOCKSIZE argument indicates the block size to use when copying the file a block at a time. It must be a positive integer, and it defaults to 1024.

delete-file

delete-file STRINGprocedure

Deletes the file with the pathname STRING. If the file does not exist, an error is signaled.

delete-file*

delete-file* STRINGprocedure

If the file with pathname STRING exists, it is deleted and #t is returned. If the file does not exist, nothing happens and #f is returned.

delete-directory

delete-directory NAME #!optional RECURSIVEprocedure

Deletes the directory with the pathname NAME. If RECURSIVE is not given or false, then the directory has to be empty.

directory

directory #!optional PATHNAME SHOW-DOTFILES?procedure

Returns a list with all files that are contained in the directory with the name PATHNAME (which defaults to the value of (current-directory)). Files beginning with . are included only if SHOW-DOTFILES? is given and not #f.

directory-exists?

directory-exists? STRINGprocedure

Returns STRING if a directory with the given pathname exists, or #f otherwise.

file-exists?

file-exists? STRINGprocedure

Returns STRING if a file or directory with the given pathname exists, or #f otherwise.

rename-file

rename-file OLD NEW #!optional CLOBBERprocedure

Renames the file or directory with the pathname OLD to NEW. If the operation does not succeed, an error is signaled.

If CLOBBER is given and not #f, NEW will be replaced when it already exists, otherwise an error is signaled.

file-readable?

file-writable?

file-executable?

file-readable? FILENAMEprocedure
file-writable? FILENAMEprocedure
file-executable? FILENAMEprocedure

These procedures return #t if the current user has read, write or execute permissions on the file named FILENAME.

Temporary files and directories

create-temporary-file

create-temporary-file #!optional EXTENSIONprocedure

Creates an empty temporary file and returns its pathname. If EXTENSION is not given, then .tmp is used. If the environment variable TMPDIR, TEMP or TMP is set, then the pathname names a file in that directory. If none of the environment variables is given, the location of the temporary file defaults to /tmp.

Note that TMPDIR, TEMP and TMP are checked in this order. It means that, for example, if both TMPDIR and TEMP are set, the value of TMPDIR will be used.

Changed in CHICKEN 5.4.0: the values of the TMPDIR, TEMP and TMP environment variables are no longer memoized (see https://bugs.call-cc.org/ticket/1830).

create-temporary-directory

create-temporary-directoryprocedure

Creates an empty temporary directory and returns its pathname. If the environment variable TMPDIR, TEMP or TMP is set, then the temporary directory is created at that location. If none of the environment variables is given, the location of the temporary directory defaults to /tmp.

Note that TMPDIR, TEMP and TMP are checked in this order. It means that, for example, if both TMPDIR and TEMP are set, the value of TMPDIR will be used.

Changed in CHICKEN 5.4.0: the values of the TMPDIR, TEMP and TMP environment variables are no longer memoized (see https://bugs.call-cc.org/ticket/1830).

Finding files

find-files

find-files DIRECTORY #!key test action seed limit dotfiles follow-symlinksprocedure

Recursively traverses the contents of DIRECTORY (which should be a string) and invokes the procedure action for all files in which the procedure test is true.

test may be a procedure of one argument or an irregex object, regex string or SRE expression that will be matched with a full pathname using irregex-match. test defaults to (constantly #t).

action should be a procedure of two arguments: the currently encountered file and the result of the previous invocation of action, or, if this is the first invocation, the value of seed. action defaults to cons, seed defaults to ().

limit should be a procedure of one argument that is called for each nested directory and which should return true, if that directory is to be traversed recursively. limit may also be an exact integer that gives the maximum recursion depth. For example, a depth of 0 means that only files in the top-level, specified directory are to be traversed. In this case, all nested directories are ignored. limit may also be #f (the default), which is equivalent to (constantly #t).

If dotfiles is given and true, then files starting with a "." character will not be ignored (but note that "." and ".." are always ignored). if follow-symlinks is given and true, then the traversal of a symbolic link that points to a directory will recursively traverse the latter. By default, symbolic links are not followed.

Note that action is called with the full pathname of each file, including the directory prefix.

glob

glob PATTERN1 ...procedure

Returns a list of the pathnames of all existing files matching PATTERN1 ..., which should be strings containing the usual file-patterns (with * matching zero or more characters and ? matching zero or one character).


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