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File input/output: Difference between revisions

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Revision as of 07:03, 11 April 2024

2,966 bytes added ,  1 month ago
m
→‎{{header|Standard ML}}
m (Update Lang example: Fix spelling of Lang)
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Line 2,116:
w/o create-file throw r>
begin
pad maxstring84 2 pick read-file throw
?dup while
pad swap 3 pick write-file throw
repeat
Line 2,126:
s" output.txt" s" input.txt" copy-file</syntaxhighlight>
 
Note the use of "2 pick" to get the input file handle and "3 pick" to get the output file handle. Local or global variables could have been used, but in this implementation simple stack manipulation was chosen. Also, only maxstring84 bytes are copied at a time, andas that is the globalmaximum guaranteed size of "pad" the global memory area is used to hold the data. For faster copies, allocating a larger buffer could be advantageous.
 
Also, abort" can be used instead of throw if desired.
Line 2,939:
i.close()
o.close()</syntaxhighlight>
 
=={{header|Nu}}==
<syntaxhighlight lang="nu">
let text = open "input.txt"
$text | save "output.txt"
</syntaxhighlight>
 
=={{header|Objeck}}==
Line 3,525 ⟶ 3,531:
 
=={{header|Rust}}==
<syntaxhighlight lang="rust">usefn std::fs::File;main() {
let contents = std::fs::read("input.txt").expect("error reading input.txt");
use std::io::{Read, Write};
std::fs::write("output.txt", contents).expect("error writing output.txt");
 
fn main() {
let mut file = File::open("input.txt").unwrap();
let mut data = Vec::new();
file.read_to_end(&mut data).unwrap();
let mut file = File::create("output.txt").unwrap();
file.write_all(&data).unwrap();
}
</syntaxhighlight>
Line 3,565:
process::exit(code);
}</syntaxhighlight>
 
=={{header|S-BASIC}}==
Surprisingly, S-BASIC has no EOF function, so we have to rely on error trapping to signal end of file. S-BASIC stores its error codes at 103H, and we can position a base-located variable there to retrieve it. The result is something of a kludge, but it works. Other S-BASIC preculiarities are explained by the comments.
<syntaxhighlight lang="BASIC">
comment
Preserve file channel #0 (the console) while declaring channels
#2 and #3 as sequential-access ASCII files.
end
files d, sa, sa
var s = string:255
based errcode = integer
base errcode at 103H
 
comment
CP/M expects upper case file names, but S-BASIC does not
automatically convert file name arguments to upper case, so we
have to do that ourself.
end
create "OUTPUT.TXT"
open #1,"INPUT.TXT"
open #2,"OUTPUT.TXT"
 
comment
S-BASIC allows alphanumeric line "numbers" (which are treated simply
as labels) as the target of GOTO and GOSUB statements, but the first
character must be a digit
end
on error goto 9done
 
rem - runtime error code 15 signals read past end of file
while errcode <> 15 do
begin
input3 #1; s
print #2; s
end
 
9done
close #1
close #2
 
end
</syntaxhighlight>
 
 
=={{header|Scala}}==
Line 3,732 ⟶ 3,775:
 
=={{header|Standard ML}}==
===Reading the whole file at once as a string===
{{works with|SML/NJ|110.59}}
{{works with|Poly/ML|5.9.1}}
<syntaxhighlight lang="sml">fun copyFile (from, to) =
<syntaxhighlight lang="sml">
(* string -> string -> bool *)
fun copyFile from to =
let
val instream = TextIO.openIn from
Line 3,742 ⟶ 3,789:
in
true
end handle _ => false;</syntaxhighlight>
===Binary mode using a buffer===
{{works with|Poly/ML|5.9.1}}
{{works with|SML/NJ|110.99.4}}
<syntaxhighlight lang="sml">
fun copyFile from to =
let
val instream = BinIO.openIn from
val outstream = BinIO.openOut to
fun aux () =
let
val buf = BinIO.inputN(instream, 1024)
in
if Word8Vector.length buf = 0
then ()
else (BinIO.output (outstream, buf); aux ())
end
in
(aux (); BinIO.closeIn instream; BinIO.closeOut outstream)
end
</syntaxhighlight>
 
=={{header|Stata}}==
Line 3,905 ⟶ 3,972:
 
fileio = ~command.files; &h.path.&h:= 'output.txt'!</syntaxhighlight>
 
=={{header|Uxntal}}==
<syntaxhighlight lang="Uxntal">|00 @System &vector $2 &expansion $2 &wst $1 &rst $1 &metadata $2 &r $2 &g $2 &b $2 &debug $1 &state $1
|10 @Console &vector $2 &read $1 &pad $4 &type $1 &write $1 &error $1
|a0 @File1 &vector $2 &success $2 &stat $2 &delete $1 &append $1 &name $2 &length $2 &read $2 &write $2
|b0 @File2 &vector $2 &success $2 &stat $2 &delete $1 &append $1 &name $2 &length $2 &read $2 &write $2
 
|0100
;in-file .File1/name DEO2
;out-file .File2/name DEO2
 
&loop
#0100 .File1/length DEO2k POP
;buffer .File1/read DEO2
.File1/success DEI2
 
.File2/length DEO2k POP
;buffer .File2/write DEO2
 
EQU2 ?&loop
 
#80 .System/state DEO
BRK
 
@in-file "input.txt 00
@out-file "output.txt 00
@buffer $100</syntaxhighlight>
 
=={{header|Vedit macro language}}==
Line 3,920 ⟶ 4,014:
 
=={{header|Wren}}==
<syntaxhighlight lang="ecmascriptwren">import "io" for File
 
var contents = File.read("input.txt")
Line 3,962 ⟶ 4,056:
 
=={{header|Zig}}==
'''Works with:''' 0.10.x, 0.11.x, 0.12.0-dev.1357+10d03acdb
 
<syntaxhighlight lang="zig">const std = @import("std");
 
pub fn main() (error{OutOfMemory} || std.fs.File.OpenError || std.fs.File.ReadError || std.fs.File.WriteError)!void {
pub fn main() !void {
var in = trygpa: std.fsheap.cwdGeneralPurposeAllocator(.{}).openFile("input.txt", = .{});
defer in_ = gpa.closedeinit();
const allocator = gpa.allocator();
var out = try std.fs.cwd().openFile("output.txt", .{ .mode = .write_only });
 
defer out.close();
varconst file_readercwd = instd.readerfs.cwd();
 
var file_writer = out.writer();
var input_file = try cwd.openFile("input.txt", .{ .mode = .read_only });
var buf: [100]u8 = undefined;
vardefer read: usize = 1input_file.close();
 
while (read > 0) {
var readoutput_file = try file_readercwd.readAllcreateFile(&buf"output.txt", .{});
defer output_file.close();
try file_writer.writeAll(buf[0..read]);
 
}
// Restrict input_file's size to "up to 10 MiB".
var input_file_content = try input_file.readToEndAlloc(allocator, 10 * 1024 * 1024);
defer allocator.free(input_file_content);
 
try output_file.writeAll(input_file_content);
return;
}</syntaxhighlight>
 
Myrmidon
23

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