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--- returning_20errors_20from_20windows_20commands [2018/03/31 14:19]
127.0.0.1 external edit
+++ returning_20errors_20from_20windows_20commands [2021/12/19 10:47]
jgharston Needs an explicit extension.
@@ Line 1: / Line 1: @@
 =====Returning errors from Windows commands=====
-//by Jonathan Harston, August 2010//\\ \\  The OSCLI command can be used to execute a Windows command. However, if the command fails, no error is generated, the Windows command interpreter merely //displays// an error message. You may see this appearing in a DOS command box before it quickly disappears.\\ \\  However, the Windows command interpreter and properly-written commands output error message to the //standard-error// output stream. This can be redirected to a file, and then any contents examined later. The following function does this.\\ \\
+//by Jonathan Harston, August 2010//\\ \\  The OSCLI command can be used to execute a Windows command. However, if the command fails, no error is generated, the Windows command interpreter merely //displays// an error message. You may see this appearing in a DOS command box before it quickly disappears.\\ \\  However, the Windows command interpreter and properly-written commands output error message to the //standard-error// output stream. This can be redirected to a file, and then any contents examined later. The following function does this.
+<code bb4w>
         DEF FNwin_cmd(cli$)
-        LOCAL ch%,err$,tmp$:tmp$=@tmp$+STR$TIME
+        LOCAL ch%,err$,tmp$:tmp$=@tmp$+STR$TIME+"."
         OSCLI "cmd /c "+cli$+" 2>"+tmp$
         ch%=OPENIN(tmp$):IF ch%=0:=""
         err$=GET$#ch%:CLOSE#ch%:OS."Delete "+tmp$
         =err$
-\\  This redirects the error output to a file, then reads that file to see if anything has been output to it. Bear in mind that if the called command displays its error reports to //standard-out// instead of //standard-error//, then it will return an empty string.\\ \\
+</code>
+This redirects the error output to a file, then reads that file to see if anything has been output to it. Bear in mind that if the called command displays its error reports to //standard-out// instead of //standard-error//, then it will return an empty string.
 ===== Examples =====
+<code>
       >PRINT FNwin_cmd("junk")
       'junk' is not recognised as an internal or external command.
@@ Line 15: / Line 21: @@
       >
-\\  Note that, as opposed to OSCLI itself, the command is //always// passed to Windows. In the second example above, the Windows **DIR** command is executed, which will result in a directory listing appearing in a DOS command box before quickly diappearing.\\ \\
+</code>
+Note that, as opposed to OSCLI itself, the command is //always// passed to Windows. In the second example above, the Windows **DIR** command is executed, which will result in a directory listing appearing in a DOS command box before quickly disappearing.
 ===== References =====
   * http://rtrussell.co.uk/bbcwin/manual/bbcwin8.html#opsys

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