September 2017 Update

Task/Truncate-a-file/AWK/truncate-a-file.awk

@@ -0,0 +1,45 @@
+# syntax: GAWK -f TRUNCATE_A_FILE.AWK
+BEGIN {
+    main("NOTHERE",100)
+    main("FILENAME.TMP",-1)
+    main("FILENAME.TMP",500)
+    exit(0)
+}
+function main(filename,size,  ret) {
+    ret = truncate_file(filename,size)
+    if (ret != "") {
+      printf("error: FILENAME=%s, %s\n",filename,ret)
+    }
+}
+function truncate_file(filename,size,  cmd,fnr,msg,old_BINMODE,old_RS,rec) {
+    cmd = sprintf("ls --full-time -o %s",filename)
+    if (size < 0) {
+      return("size cannot be negative")
+    }
+    old_BINMODE = BINMODE
+    old_RS = RS
+    BINMODE = 3
+    RS = "[^\x00-\xFF]"
+    while (getline rec <filename > 0) {
+      fnr++
+    }
+    close(filename)
+    if (fnr == 0) {
+      msg = "file not found"
+    }
+    if (fnr > 1) {
+      msg = "choose a different RecordSeparator"
+    }
+    if (msg == "") { # no errors
+      system(cmd) # optional: show filesize before truncation
+      if (length(rec) > size) {
+        rec = substr(rec,1,size)
+      }
+      printf("%s",rec) >filename
+      close(filename)
+      system(cmd) # optional: show filesize after truncation
+    }
+    BINMODE = old_BINMODE
+    RS = old_RS
+    return(msg)
+}

Task/Truncate-a-file/C++/truncate-a-file.cpp

@@ -0,0 +1,20 @@
+#include <string>
+#include <fstream>
+
+using namespace std;
+
+void truncateFile(string filename, int max_size) {
+  std::ifstream input( filename, std::ios::binary );
+  char buffer;
+  string outfile = filename + ".trunc";
+  ofstream appendFile(outfile, ios_base::out);
+  for(int i=0; i<max_size; i++) {
+    input.read( &buffer, sizeof(buffer) );
+    appendFile.write(&buffer,1);
+  }
+  appendFile.close();                                                                                                                                                                }
+
+int main () {
+  truncateFile("test.txt", 5);
+  return 0;
+}

Task/Truncate-a-file/Elena/truncate-a-file.elena

@@ -1,29 +1,28 @@
-#import system.
-#import system'io.
-#import extensions.
+import system'io.
+import extensions.
 
-#class(extension:file_path)fileOp
+file_info extension fileOp
 {
-    #method set &length:length
+    set length:length
     [
-        #var(type:stream)stream := FileStream openForEdit &path:self.
+        stream stream := FileStream openForEdit:self.
 
-        stream set &length:length.
+        stream set length:length.
 
         stream close.
     ]
 }
 
-#symbol program =
+program =
 [
-    ('program'arguments length != 3)?
-        [  console << "Please provide the path to the file and a new length". #throw AbortException new. ].
+    if ('program'arguments length != 3)
+        [  console printLine:"Please provide the path to the file and a new length". AbortException new; raise ].
 
-    #var fileName := 'program'arguments@1.
-    #var length := ('program'arguments@2) toInt.
+    file_info file := File new('program'arguments[1]).
+    var length := 'program'arguments[2] toInt.
 
-    (fileName file_path is &available)
-        ! [ console writeLine:"File ":fileName:" does not exist". #throw AbortException new. ].
+    ifnot (file isAvailable)
+        [ console printLine("File ",file," does not exist"). AbortException new; raise ].
 
-    fileName file_path set &length:length.
+    file set length:length.
 ].

Task/Truncate-a-file/Kotlin/truncate-a-file.kotlin

@@ -0,0 +1,25 @@
+// version 1.1.2
+
+import java.io.FileOutputStream
+import java.nio.channels.FileChannel
+
+fun truncateFile(fileName: String, newSize: Long) {
+    var fc: FileChannel? = null
+    try {
+        fc = FileOutputStream(fileName, true).channel
+        if (newSize >= fc.size())
+            println("Requested file size isn't less than existing size")
+        else
+            fc.truncate(newSize)
+    }
+    catch (ex: Exception) {
+        println(ex.message)
+    }
+    finally {
+        fc!!.close()
+    }
+}
+
+fun main(args: Array<String>) {
+    truncateFile("test.txt", 10)
+}

Task/Truncate-a-file/PowerShell/truncate-a-file.psh

@@ -0,0 +1,3 @@
+Function Truncate-File(fname) {
+   $null | Set-Content -Path "$fname"
+}

Task/Truncate-a-file/Python/truncate-a-file.py

@@ -5,5 +5,4 @@ def truncate_file(name, length):
         return False
     with open(name, 'ab') as f:
         f.truncate(length)
-        f.close()
-        return True
+    return True