2.4.1.1. - System Functions

chdir()

Changes spec's current working directory to to the user's home directory as obtained from the user's environment variable HOME. Returns true or false according to whether the command was successful or not. The value of the built-in string variable CWD is updated to the current working directory.

chdir(directory)

As above, but changes to the directory directory, which must be a string constant or expression.

unix()

Spawns an interactive subshell using the program obtained from the user's environment variable SHELL (or shell). Uses /bin/sh if the environment variable is not set. Returns the integer exit status of the shell.

unix(command)

As above, but uses /bin/sh to execute the one-line command command, which must be a string constant or expression. Returns the integer exit status of the command.

unix(command, str [, len ])

As above, but the argument str is the name of a variable in which to place the string output from the command in the first argument. The maximum length of the string is 4096 bytes (including a null byte). The optional third argument can be used to specify a larger size.

time()

Returns the current epoch in seconds. The UNIX epoch is the number of seconds from January 1, 1970, 00:00:00 GMT. The value returned includes a fractional part with the resolution dependent on the host platform. Millisecond resolution is standard, although on 80X86 systems only hundredth of a second resolution is returned.

date()

Returns a string containing the current date as

Thu Jul 23 21:12:39 EDT 1992 .

date(seconds)

As above, but the returned string represents the epoch given by seconds. See time() above.