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diff --git a/doc/sources/unix-other.texi b/doc/sources/unix-other.texi deleted file mode 100644 index 7b810d5d6..000000000 --- a/doc/sources/unix-other.texi +++ /dev/null @@ -1,132 +0,0 @@ -@node Other Unix -@chapter Other Unix-specific facilities - -@menu -* Expect:: Expect, for pattern matching from a port. -@end menu - -@node Expect -@section Expect: Pattern Matching from a Port - -@code{expect} is a macro for selecting actions based on the output from -a port. The name comes from a tool of similar functionality by Don Libes. -Actions can be taken when a particular string is matched, when a timeout -occurs, or when end-of-file is seen on the port. The @code{expect} macro -is described below; @code{expect-strings} is a front-end to @code{expect} -based on regexec @xref{Regular expressions}. - -Using these macros requires for now: -@smalllisp -(load-from-path "ice-9/expect") -@end smalllisp - -@defun expect-strings clause @dots{} -By default, @code{expect-strings} will read from the current input port. -The first term in each clause consists of an expression evaluating to -a string pattern (regular expression). As characters -are read one-by-one from the port, they are accumulated in a buffer string -which is matched against each of the patterns. When a -pattern matches, the remaining expression(s) in -the clause are evaluated and the value of the last is returned. For example: - -@smalllisp -(with-input-from-file "/etc/passwd" - (lambda () - (expect-strings - ("^nobody" (display "Got a nobody user.\n") - (display "That's no problem.\n")) - ("^daemon" (display "Got a daemon user.\n"))))) -@end smalllisp - -The regular expression is compiled with the @code{REG_NEWLINE} flag, so -that the @code{^} and @code{$} anchors will match at any newline, not -just at the start -and end of the string. - -There are two other ways to write a clause: - -The expression(s) to evaluate on a match -can be omitted, in which case the result of the match -(converted to strings, as obtained from regexec with @var{match-pick} -set to @code{""}) will be returned if the pattern matches. - -The symbol @code{=>} can be used to indicate that there is a single -expression to evaluate on a match, which must be a -procedure which will accept the result of a successful match (converted -to strings, as obtained from regexec with @var{match-pick} set to -@code{""}). E.g., - -@smalllisp -("^daemon" => write) -("^d\\(aemon\\)" => (lambda args (map write args))) -("^da\\(em\\)on" => (lambda (all sub) - (write all) - (write sub))) -@end smalllisp - -The order of the substrings corresponds to the order in which the -opening brackets occur in the regular expression. - -A number of variables can be used to control the behaviour -of @code{expect} (and @code{expect-strings}). -By default they are all bound at the top level to -the value @code{#f}, which produces the default behaviour. -They can be redefined at the -top level or locally bound in a form enclosing the @code{expect} expression. - -@table @code -@item expect-port -A port to read characters from, instead of the current input port. -@item expect-timeout -@code{expect} will terminate after this number of -seconds, returning @code{#f} or the value returned by -@code{expect-timeout-proc}. -@item expect-timeout-proc -A procedure called if timeout occurs. The procedure takes a single argument: -the accumulated string. -@item expect-eof-proc -A procedure called if end-of-file is detected on the input port. The -procedure takes a single argument: the accumulated string. -@item expect-char-proc -A procedure to be called every time a character is read from the -port. The procedure takes a single argument: the character which was read. -@end table - -Here's an example using all of the variables: - -@smalllisp -(let ((expect-port (open-input-file "/etc/passwd")) - (expect-timeout 1) - (expect-timeout-proc - (lambda (s) (display "Times up!\n"))) - (expect-eof-proc - (lambda (s) (display "Reached the end of the file!\n"))) - (expect-char-proc display)) - (expect-strings - ("^nobody" (display "Got a nobody user\n")))) -@end smalllisp -@end defun - -@defun expect clause @dots{} -@code{expect} is used in the same way as @code{expect-strings}, -but tests are specified not as patterns, but as procedures. The -procedures are called in turn after each character is read from the -port, with the value of the accumulated string as the argument. The -test is successful if the procedure returns a non-false value. - -If the @code{=>} syntax is used, then if the test succeeds it must return -a list containing the arguments to be provided to the corresponding -expression. - -In the following example, a string will only be matched at the beginning -of the file: -@smalllisp -(let ((expect-port (open-input-file "/etc/passwd"))) - (expect - ((lambda (s) (string=? s "fnord!")) - (display "Got a nobody user!\n")))) -@end smalllisp - -The control variables described for @code{expect-strings} can also -be used with @code{expect}. -@end defun |