I am writing the auto-build system for the one complicated Qt5 program.
Some of it's C++ sources contains special markers and need to be processed by the external utility.
So i decide to write a custom prebuild step in qmake project like this:
!build_pass {
win32 {
for( src, SOURCES ) {
system("findstr \"MY_CUSTOM_MARKER\" $$src"):system( MyExternalUtil $$src )
}
}
}
But first system command always return success, i.e. all of my sources will be processed!
However, official Qt documentation say they should not.
So my question is: why such system command always returns 0?
P.S. I tried it in the Windows command prompt: findstr properly set %errorlevel% to the 1 when specified text was not found.
P.P.S Here is the workaround(just use other version of system):
!build_pass {
win32 {
for( SRC_PATH, SOURCES ) {
FULL_SRC_PATH = \"$$PWD/$$SRC_PATH\"
FULL_SRC_PATH = $$replace( FULL_SRC_PATH, /, \ )
FIND_RES = $$system( findstr \"MY_CUSTOM_MARKER\" $$FULL_SRC_PATH )
!isEmpty( FIND_RES ) {
message( Processing $$SRC_PATH... )
system( MyExternalUtil $$FULL_SRC_PATH )
}
}
}
}
defineTest(systemWrapper) {
ret = $$system($${ARGS} 2> /dev/null; echo $?)
equals(ret, 0):return(true)
return(false)
}
Related
I have an experience with C#, where I can work with commands from user like this:
string command;
while ( (command = GetCommandFromUser()) != EXIT_COMMAND )
ProcessCommand(command);
This simple code allows me get command from user (from Console or something like this) and process it.
But in Go I have only this code:
var command string
for command = GetCommandFromUser(); command != ExitCommand; command = GetCommandFromUser() {
ProcessCommand(command)
}
Can I do it simply?
for {
command := GetCommandFromUser()
if command == ExitCommand {
break
}
ProcessCommand(command)
}
I am developing a lexer for F++ language using Cygwin terminal and flex tools on Windows 8 OS.
The problem I met and I am having hard time to solve is the case of multiple input buffers.
Let's say I have an F++ file with a #include test.h header. My lexer then have to open the
test.h file and recognize its tokens before it proceeds to the file etc.
My lexer uses fopen function to open header files but fopen returns null even if my file exists.
I quote my code.
**<incl>[ \t]* /* eat the whitespace */
<incl>[^ \t\n]+ { /* got the include file name */
if ( include_stack_ptr >= MAX_INCLUDE_DEPTH )
{
fprintf( stderr, "Includes nested too deeply" );
exit( 1 );
}
include_stack[include_stack_ptr++] =YY_CURRENT_BUFFER;
if( (yyin = fopen( yytext, "r,ccs=ccs=UTF-8")) !=NULL)
{
printf("Successful opening %s in mode r.\n",yytext);
}else{
fprintf(stderr, "\nError opening file %s in mode r.\n",yytext);
}
yy_switch_to_buffer(yy_create_buffer( yyin, YY_BUF_SIZE ) );
printf("testpoint4");
BEGIN(INITIAL);
printf("testpoint5");
}
<<EOF>> {
if ( (include_stack_ptr--)==0 ){
printf("here");
yyterminate();
}else{
printf("edw2");
yy_delete_buffer( YY_CURRENT_BUFFER );
yy_switch_to_buffer(include_stack[include_stack_ptr] );
}
}
%%
main()
{ yylex(); }**
Check the line: fopen( yytext, "r,ccs=ccs=UTF-8")
use a filename that does not have a comma in it.
for an abundance of caution, try a trivial file name, like foo.fpp
if the file opens, the problem is in the permitted characters for files on your filesystem/OS.
I'm using D as a scripting language for Windows 7 console stuff to automate boring tasks. One of my scripts (open.exe) is supposed to allow me to open stuff from the command line without me having to specify which program I use (I have a configuration file with this stuff). Now, I use executeShell to do this, and call something like start [name of program I want to use] [name of input file]. If I do this directly from the shell, it returns immediately, but if I do it using my D script, it doesn't return until the program that it opens is closed. What should I do to allow it to return immediately?
For reference purposes, this is the business logic of my script (the main method just does some argument parsing for piping purposes):
immutable path = "some//path//going//to//config//file.conf";
void process(string input) {
string extension = split(input,".")[1]; //get file extension from input
auto config = File(path,"r"); auto found = false;
while (!config.eof()){
auto line = chomp(config.readln());
if (line[0]!='#') { //skip comment lines
auto divided = split(line, ":");
if (divided[0] == extension) {
found = true;
auto command = "start " ~ divided[1] ~ " " ~ input;
auto result = executeShell(command);
//test for error code and output if necessary
writeln(result.output);
}
}
}
if (!found)
writeln("ERROR: Don't know how to open " ~ input);
}
From the top of the std.process documentation:
Execute and wait for completion, collect output - executeShell
The Windows start program spawns a process and exits immediately. D's executeShell does something else. If you'd like to spawn another program, use the appropriate functions: spawnProcess or spawnShell.
Why would I need this?
The location of a datum keeps changing because input data varies too much, so other than printing it, sleeping for 30 seconds so I can manually enter it into GDB, then continuing the program, it might be useful to just let the program tell GDB where to watch.
But is such a thing possible?
You can get close; assuming for simplicity C/C++ language
Define a function that returns a reference to your datum to track:
// debug.h
extern "C" mydatastruct* GetDatumForDebug();
// debug.cpp
mydatastruct* GetDatumForDebug()
{
if (s_initialized)
return &some_complicated_address_lookup_perhaps_in_Cpp_or_java_orwhatever();
return (mydatastruct*) 0;
}
You can then subsequently just
(gdb) display GetDatumForDebug()
or even
(gdb) display GetDatumForDebug()->s
I assume it will be possible to use the result of GetDatumForDebug() in your debug watches, I'm not sure what you do/how you do that :)
Here is a working example, crammed in a single source (test.cpp) for speed: compile with g++ -g test.cpp -o test:
static bool s_initialized = false;
struct mydatastruct { const char* s; };
static mydatastruct& some_complicated_address_lookup_perhaps_in_Cpp_or_java_orwhatever()
{
static mydatastruct s_instance = { "hello world" };
s_initialized = true;
return s_instance;
}
extern "C" mydatastruct* GetDatumForDebug();
// debug.cpp
mydatastruct* GetDatumForDebug()
{
if (s_initialized)
return &some_complicated_address_lookup_perhaps_in_Cpp_or_java_orwhatever();
return (mydatastruct*) 0;
}
int main()
{
// force initialize for demo purpose:
some_complicated_address_lookup_perhaps_in_Cpp_or_java_orwhatever();
return 42;
}
Automate gdb commands
Append the following to .gdbinit in your working directory:
break main
run
call some_complicated_address_lookup_perhaps_in_Cpp_or_java_orwhatever()
display GetDatumForDebug()? GetDatumForDebug()->s : ""
This will automatically execute these commands on launching gdb in that directory
I've got a Windows XP batch script which cleans some directories, but I would like to move the deleted files to trash instead of using plain del. How is this done?
It looks like the only languages I can use for this is plain batch or Perl.
use Win32::FileOp qw(Recycle);
Recycle(#ARGV);
Write a VBS script (Original Link) then call it with MyDelScript.vbs
function main()
{
if (WScript.Arguments.length != 1)
{
WScript.Echo("<Insert informative error message here>");
return;
}
var Path = WScript.Arguments(0);
var Shell = WScript.CreateObject("Shell.Application");
var Item = Shell.Namespace(0).ParseName(Path);
Item.InvokeVerb("delete");
}
The Win32::FileOp module has a Recycle function. From the docs:
Recycle #filenames
Send the files into the recycle bin. You will not get any confirmation dialogs.
Returns true if successful.
It can be done like this with plain batch and embedded VBScript. Put the following code into a file called recycle.cmd:
<!-- : Begin batch script
#echo off
if "%1"=="" (
echo Usage: %~nx0 FILE_TO_RECYCLE[...]
echo This script puts files into the recycle bin
exit /b 1
)
cscript //nologo "%~f0?.wsf" %*
exit /b %errorlevel%
----- Begin embedded wsf script --->
<job><script language="VBScript">
Set app = WScript.CreateObject("Shell.Application")
Set fso = CreateObject("Scripting.FileSystemObject")
For Each arg In WScript.Arguments
If fso.FileExists(arg) Then
Set file = fso.GetFile(arg)
Set folderItem = app.Namespace(0).ParseName(file.Path)
folderItem.InvokeVerb("delete")
Else
WScript.Echo "File not found: " & arg
End If
Next
</script></job>
Example:
echo This file is dirt.> dirt.txt
echo This file is trash.> trash.txt
recycle dirt.txt trash.txt
As you can see the script allows recycling multiple files with one command.
It does not suppport the wildcards * and ? though.
The idea of embedding VBScript inside a batch file is taken from dbenham's answer to Is it possible to embed and execute VBScript within a batch file without using a temporary file? (scroll down to UPDATE 2014-04-27).
You could use the "recycle" utility which is part of CmdUtils from MaDdoG Software. From the page listing -
Recycle, a safe replacement for the DEL command, that sends files to the recycle bin instead of deleting them. Recycle is also more flexible than DEL; you can specify multiple files at once (or use wildcards), and you can recycle whole directories at once (be careful!)
I would suggest you try its various switches before you incorporate it into your script - there is quite a bit of deviation from the default behaviour of the "del" command.
UPDATE: Contrary to my original claim that the following code does not work, it indeed seems to work. I just forgot that the file I wanted to delete was not in $ENV{TEMP} but a subdirectory of $ENV{TEMP}. The problem is, the file does not go to the Recycle Bin.
The right solution is to use Win32::FileOp but I am going to leave this script here as an example of how to use Win32::API and Win32::API::Struct. I would appreciate it if anyone can point out what I am doing wrong. For your reference:
SHFileOperation: http://msdn.microsoft.com/en-us/library/bb762164(VS.85).aspx
LPSHFILEOPSTRUCT: http://msdn.microsoft.com/en-us/library/bb759795(VS.85).aspx
#!/usr/bin/perl
use strict;
use warnings;
use File::Spec::Functions qw( catfile );
use Win32::API;
Win32::API::Struct->typedef(
SHFILEOPSTRUCT => qw(
HWND hwnd;
UINT wFunc;
LPCTSTR pFrom;
LPCTSTR pTo;
FILEOP_FLAGS fFlags;
BOOL fAnyOperationsAborted;
LPVOID hNameMappings;
LPCTSTR lpszProgressTitle;
)
);
Win32::API->Import(
shell32 => q{ int SHFileOperation( LPSHFILEOPSTRUCT lpFileOp ) }
);
my $op = Win32::API::Struct->new( 'SHFILEOPSTRUCT' );
$op->{wFunc} = 0x0003; # FO_DELETE from ShellAPI.h
$op->{fFlags} = 0x0040; # FOF_ALLOWUNDO from ShellAPI.h
my $to_delete = catfile( $ENV{TEMP}, "test.file" );
$op->{pFrom} = $to_delete . "\0\0";
my $result = SHFileOperation( $op );
if ( $result ) {
warn sprintf "The operation failed: %4.4X\n", $result;
}
else {
if ( $op->{fAnyOperationsAborted} ) {
warn "Operation was aborted\n";
}
else {
warn "The operation succeeded\n";
}
}
__END__