File and Time Extensions for TinyScheme (FTX) 1.0 [August, 2004] Based on the TinyScheme Extensions (TSX) 1.1 [September, 2002] (c) 2002 Manuel Heras-Gilsanz (manuel@heras-gilsanz.com) This software is subject to the license terms contained in the LICENSE file. TSX FUNCTIONS TSX incorporates the following functions: *File system (included if HAVE_FILESYSTEM is defined in tsx.h) Scheme already defines functions to read and write files. These functions allow access to the filesystem to check if a certain file exists, to get its size, etc. In addition to these functions, a string constant DIR-SEPARATOR has been defined. It should be used in scripts which build file names that include one or more directories to keep the scripts portable to different operating systems. (file-exists? filename) filename: string This function returns #t if the indicated file exists, and #f if it does not exist or if it is not accessible to the requesting user. Accessibility is based on the real user and group ID rather than the effective user ID and group ID. (file-type filename) filename: string This function returns a value based on the file type. It returns FILE_TYPE_FILE (1) for regular files, FILE_TYPE_DIR (2) for directories, and FILE_TYPE_LINK (3) for symbolic links. The value FILE_TYPE_OTHER (0) is returned if the file is of some other type, does not exist, or if the user does not have sufficient privileges to allow the file type to be determined. (file-size filename) filename: string This function returns the size (in bytes) of the indicated file, or #f if the file does not exists or is not accessible to the requesting user. (file-delete filename) filename: string Removes the specified file. It returns #t if the operation succeeds, or #f otherwise (e.g., because the file is read-only, or because the file does not exist). (dir-open-stream path) path: string Opens a "directory stream" on the provided directory path. This stream will provide all the files within the directory, using the function read-dir-entry. The stream should be closed at the end with dir-close-stream. (dir-read-entry dirstream) dirstream: directory stream, obtained with dir-open-stream. It returns the name of the following directory entry, or eof if all the entries were provided. Check the return value with with eof-object?. (dir-rewind dirstream) dirstream: directory stream, obtained with dir-open-stream. Resets the given directory stream. The next call to dir-read-entry will return the first entry again. It returns #t if the operation succeeds, or #f otherwise (ie. dirstream not valid).. (dir-close-stream dirstream) dirstream: directory stream, obtained with dir-open-stream. Close directory stream. No further calls to read-dir-entry should be performed. *Time (available if HAVE_TIME is defined in tsx.h) (time) Returns the current local time, as a list of integer containing: (year month day-of-month hour min sec millisec) The year is expressed as an offset from 1900. (gettimeofday) Returns a list containing the number of seconds from the beginning of the day, and microseconds within the current second. (usleep microsec) microsec: integer Suspends execution of the calling thread during the specified number of microseconds. END