How to pass vector to pointer array winapi?
0
I want to stop using manual allocated memory to work with all winapi. for testing i try to change my code. but i get
no suitable conversion from vector DWORD to DWORD * exists.
std::vector<DWORD> aProcesses;
DWORD cbNeeded;
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
{
return 1;
}
for (auto& p : aProcesses)
{
std::cout << p << std::endl;
}
Manual Allocated memory below
DWORD aProcesses[1024], cbNeeded, cProcesses;
unsigned int i;
if (!EnumProcesses(aProcesses, sizeof(aProcesses), &cbNeeded))
{
return 1;
}
// Calculate how many process identifiers were returned.
cProcesses = cbNeeded / sizeof(DWORD);
// Print the name and process identifier for each process.
for (i = 0; i < cProcesses; i++)
{
if (aProcesses[i] != 0)
{
std::cout << aProcesses[i] << std::endl;
}
c++ windows visual-studio winapi
asked Nov 15 '18 at 4:43
Dwerson buschDwerson busch
64
|
show 3 more comments
0
I want to stop using manual allocated memory to work with all winapi. for testing i try to change my code. but i get
no suitable conversion from vector DWORD to DWORD * exists.
std::vector<DWORD> aProcesses;
DWORD cbNeeded;
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
{
return 1;
}
for (auto& p : aProcesses)
{
std::cout << p << std::endl;
}
Manual Allocated memory below
DWORD aProcesses[1024], cbNeeded, cProcesses;
unsigned int i;
if (!EnumProcesses(aProcesses, sizeof(aProcesses), &cbNeeded))
{
return 1;
}
// Calculate how many process identifiers were returned.
cProcesses = cbNeeded / sizeof(DWORD);
// Print the name and process identifier for each process.
for (i = 0; i < cProcesses; i++)
{
if (aProcesses[i] != 0)
{
std::cout << aProcesses[i] << std::endl;
}
c++ windows visual-studio winapi
asked Nov 15 '18 at 4:43
Dwerson buschDwerson busch
64
2
instead of aProcesses` useaProcesses.data()or alternately&aProcesses[0]see: en.cppreference.com/w/cpp/container/vector/data
– doug
Nov 15 '18 at 4:48
1
Note that you need to callresize()on the vector yourself before passing a pointer to the data buffer to an API function, since Windows doesn't know anything about c++.
– Jonathan Potter
Nov 15 '18 at 4:51
It would be helpful to include the code you anticipate replacing to provide more specific advice.
– doug
Nov 15 '18 at 4:58
@doug i include manual allocate memory ways
– Dwerson busch
Nov 15 '18 at 5:04
Just declare your vector like so:std::vector<DWORD> aProcesses(1024);and useaProcesses.data()which is a pointer to the first vector element.
– doug
Nov 15 '18 at 5:08
|
show 3 more comments
0
0
0
I want to stop using manual allocated memory to work with all winapi. for testing i try to change my code. but i get
no suitable conversion from vector DWORD to DWORD * exists.
std::vector<DWORD> aProcesses;
DWORD cbNeeded;
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
{
return 1;
}
for (auto& p : aProcesses)
{
std::cout << p << std::endl;
}
Manual Allocated memory below
DWORD aProcesses[1024], cbNeeded, cProcesses;
unsigned int i;
if (!EnumProcesses(aProcesses, sizeof(aProcesses), &cbNeeded))
{
return 1;
}
// Calculate how many process identifiers were returned.
cProcesses = cbNeeded / sizeof(DWORD);
// Print the name and process identifier for each process.
for (i = 0; i < cProcesses; i++)
{
if (aProcesses[i] != 0)
{
std::cout << aProcesses[i] << std::endl;
}
c++ windows visual-studio winapi
asked Nov 15 '18 at 4:43
Dwerson buschDwerson busch
64
I want to stop using manual allocated memory to work with all winapi. for testing i try to change my code. but i get
no suitable conversion from vector DWORD to DWORD * exists.
std::vector<DWORD> aProcesses;
DWORD cbNeeded;
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
{
return 1;
}
for (auto& p : aProcesses)
{
std::cout << p << std::endl;
}
Manual Allocated memory below
DWORD aProcesses[1024], cbNeeded, cProcesses;
unsigned int i;
if (!EnumProcesses(aProcesses, sizeof(aProcesses), &cbNeeded))
{
return 1;
}
// Calculate how many process identifiers were returned.
cProcesses = cbNeeded / sizeof(DWORD);
// Print the name and process identifier for each process.
for (i = 0; i < cProcesses; i++)
{
if (aProcesses[i] != 0)
{
std::cout << aProcesses[i] << std::endl;
}
c++ windows visual-studio winapi
c++ windows visual-studio winapi
asked Nov 15 '18 at 4:43
Dwerson buschDwerson busch
64
asked Nov 15 '18 at 4:43
Dwerson buschDwerson busch
64
edited Nov 15 '18 at 5:02
Dwerson busch
asked Nov 15 '18 at 4:43
Dwerson buschDwerson busch
64
asked Nov 15 '18 at 4:43
Dwerson buschDwerson busch
64
asked Nov 15 '18 at 4:43
Dwerson buschDwerson busch
64
64
2
instead of aProcesses` useaProcesses.data()or alternately&aProcesses[0]see: en.cppreference.com/w/cpp/container/vector/data
– doug
Nov 15 '18 at 4:48
1
Note that you need to callresize()on the vector yourself before passing a pointer to the data buffer to an API function, since Windows doesn't know anything about c++.
– Jonathan Potter
Nov 15 '18 at 4:51
It would be helpful to include the code you anticipate replacing to provide more specific advice.
– doug
Nov 15 '18 at 4:58
@doug i include manual allocate memory ways
– Dwerson busch
Nov 15 '18 at 5:04
Just declare your vector like so:std::vector<DWORD> aProcesses(1024);and useaProcesses.data()which is a pointer to the first vector element.
– doug
Nov 15 '18 at 5:08
|
show 3 more comments
2
instead of aProcesses` useaProcesses.data()or alternately&aProcesses[0]see: en.cppreference.com/w/cpp/container/vector/data
– doug
Nov 15 '18 at 4:48
1
Note that you need to callresize()on the vector yourself before passing a pointer to the data buffer to an API function, since Windows doesn't know anything about c++.
– Jonathan Potter
Nov 15 '18 at 4:51
It would be helpful to include the code you anticipate replacing to provide more specific advice.
– doug
Nov 15 '18 at 4:58
@doug i include manual allocate memory ways
– Dwerson busch
Nov 15 '18 at 5:04
Just declare your vector like so:std::vector<DWORD> aProcesses(1024);and useaProcesses.data()which is a pointer to the first vector element.
– doug
Nov 15 '18 at 5:08
2
2
instead of aProcesses` use
aProcesses.data() or alternately &aProcesses[0] see: en.cppreference.com/w/cpp/container/vector/data– doug
Nov 15 '18 at 4:48
instead of aProcesses` use
aProcesses.data() or alternately &aProcesses[0] see: en.cppreference.com/w/cpp/container/vector/data– doug
Nov 15 '18 at 4:48
1
1
Note that you need to call
resize() on the vector yourself before passing a pointer to the data buffer to an API function, since Windows doesn't know anything about c++.– Jonathan Potter
Nov 15 '18 at 4:51
Note that you need to call
resize() on the vector yourself before passing a pointer to the data buffer to an API function, since Windows doesn't know anything about c++.– Jonathan Potter
Nov 15 '18 at 4:51
It would be helpful to include the code you anticipate replacing to provide more specific advice.
– doug
Nov 15 '18 at 4:58
It would be helpful to include the code you anticipate replacing to provide more specific advice.
– doug
Nov 15 '18 at 4:58
@doug i include manual allocate memory ways
– Dwerson busch
Nov 15 '18 at 5:04
@doug i include manual allocate memory ways
– Dwerson busch
Nov 15 '18 at 5:04
Just declare your vector like so:
std::vector<DWORD> aProcesses(1024); and use aProcesses.data() which is a pointer to the first vector element.– doug
Nov 15 '18 at 5:08
Just declare your vector like so:
std::vector<DWORD> aProcesses(1024); and use aProcesses.data() which is a pointer to the first vector element.– doug
Nov 15 '18 at 5:08
|
show 3 more comments
2 Answers
2
active
oldest
votes
0
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
won't work well. First thing is, you need to pass aProcesses.data() as the first parameter and the number of *bytes* aProcess can hold as the 2nd: aProcesses.size() * sizeof(DOWD).
If cbNeeded >= aProcess.size() * sizeof(DWORD) after the call, you have to resize the vector to cbNeeded / sizeof(DWORD) and call EnumProcesses() again to make sure you got all processes.
answered Nov 15 '18 at 5:06
SwordfishSwordfish
10.2k11436
if like that. is it call EnumProcesses twice. it make execution slow?
– Dwerson busch
Nov 15 '18 at 5:20
You have no other choice if you don't pass an array that is big enough the first time you callEnumProcesses().
– Swordfish
Nov 15 '18 at 5:44
add a comment |
0
A vector isn't a pointer to DWORD; however, this vector happens to contain one so you can
if (!EnumProcesses(aProcesses.data(), aProcesses.capacity(), &cbNeeded))
if your compiler is compiling for the C++11 Standard revision or more recent or
if (!EnumProcesses(&aProcesses[0], aProcesses.capacity(), &cbNeeded))
if it is not.
But that just gets things compiling
There are logic problems yet to be dealt with.
const int MAX_PROCESSES = 1024; // very few Windows systems will exceed 1024 processes
std::vector<DWORD> aProcesses(MAX_PROCESSES); // allocate space
DWORD cbNeeded;
if (!EnumProcesses(aProcesses.data(),
aProcesses.capacity() * sizeof(DWORD), // size in bytes, not elements
&cbNeeded))
{
return 1;
}
//for (auto& p : aProcesses) Not all processes may have been filled. The unused portions
//are zeroed, so this is safe, but wasteful
for (int i = 0; i < cbNeeded / sizeof(DWORD); ++i)
{
std::cout << aProcesses[i] << std::endl;
}
answered Nov 15 '18 at 4:51
user4581301user4581301
20.5k51931
is not MAX_NUM_DWORDS macro manually allocated memory? i should knows max possible the value?
– Dwerson busch
Nov 15 '18 at 5:06
@Dwersonbusch No, that was a stub. There is pretty much no way to know how many processes are running, but this rarely gets above a few hundred on all but the busiest of servers. Will update question.
– user4581301
Nov 15 '18 at 5:12
EnumProcesses api it just example. i knows if max processes will not run above 1k. but there's other winapi it will return above 1k value.
– Dwerson busch
Nov 15 '18 at 5:18
Why do you say that&aProcesses[0]isn't legal?aProcesses[0]returns a reference,T&, and taking the address of a reference is just a pointer to the referenced object. A DWORD in this case.
– doug
Nov 15 '18 at 5:58
@doug I can't imagine how you could dovectorand theoverload so that&vec[0]won't work, but it's not guaranteed. It's only an issue with C++ 98 and 03, so I did some old school standard diving and in 2005 drafts the wording looks like obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size(). Looks pretty conclusive that it ought to work and I'm gonna have to stop. It's too damn late and I work in the morning. And I'm having trouble typing work. Always a bad sign.
– user4581301
Nov 15 '18 at 6:59
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
won't work well. First thing is, you need to pass aProcesses.data() as the first parameter and the number of *bytes* aProcess can hold as the 2nd: aProcesses.size() * sizeof(DOWD).
If cbNeeded >= aProcess.size() * sizeof(DWORD) after the call, you have to resize the vector to cbNeeded / sizeof(DWORD) and call EnumProcesses() again to make sure you got all processes.
answered Nov 15 '18 at 5:06
SwordfishSwordfish
10.2k11436
if like that. is it call EnumProcesses twice. it make execution slow?
– Dwerson busch
Nov 15 '18 at 5:20
You have no other choice if you don't pass an array that is big enough the first time you callEnumProcesses().
– Swordfish
Nov 15 '18 at 5:44
add a comment |
0
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
won't work well. First thing is, you need to pass aProcesses.data() as the first parameter and the number of *bytes* aProcess can hold as the 2nd: aProcesses.size() * sizeof(DOWD).
If cbNeeded >= aProcess.size() * sizeof(DWORD) after the call, you have to resize the vector to cbNeeded / sizeof(DWORD) and call EnumProcesses() again to make sure you got all processes.
answered Nov 15 '18 at 5:06
SwordfishSwordfish
10.2k11436
if like that. is it call EnumProcesses twice. it make execution slow?
– Dwerson busch
Nov 15 '18 at 5:20
You have no other choice if you don't pass an array that is big enough the first time you callEnumProcesses().
– Swordfish
Nov 15 '18 at 5:44
add a comment |
0
0
0
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
won't work well. First thing is, you need to pass aProcesses.data() as the first parameter and the number of *bytes* aProcess can hold as the 2nd: aProcesses.size() * sizeof(DOWD).
If cbNeeded >= aProcess.size() * sizeof(DWORD) after the call, you have to resize the vector to cbNeeded / sizeof(DWORD) and call EnumProcesses() again to make sure you got all processes.
answered Nov 15 '18 at 5:06
SwordfishSwordfish
10.2k11436
if (!EnumProcesses(aProcesses, aProcesses.capacity(), &cbNeeded))
won't work well. First thing is, you need to pass aProcesses.data() as the first parameter and the number of *bytes* aProcess can hold as the 2nd: aProcesses.size() * sizeof(DOWD).
If cbNeeded >= aProcess.size() * sizeof(DWORD) after the call, you have to resize the vector to cbNeeded / sizeof(DWORD) and call EnumProcesses() again to make sure you got all processes.
answered Nov 15 '18 at 5:06
SwordfishSwordfish
10.2k11436
answered Nov 15 '18 at 5:06
SwordfishSwordfish
10.2k11436
answered Nov 15 '18 at 5:06
SwordfishSwordfish
10.2k11436
answered Nov 15 '18 at 5:06
SwordfishSwordfish
10.2k11436
10.2k11436
if like that. is it call EnumProcesses twice. it make execution slow?
– Dwerson busch
Nov 15 '18 at 5:20
You have no other choice if you don't pass an array that is big enough the first time you callEnumProcesses().
– Swordfish
Nov 15 '18 at 5:44
add a comment |
if like that. is it call EnumProcesses twice. it make execution slow?
– Dwerson busch
Nov 15 '18 at 5:20
You have no other choice if you don't pass an array that is big enough the first time you callEnumProcesses().
– Swordfish
Nov 15 '18 at 5:44
if like that. is it call EnumProcesses twice. it make execution slow?
– Dwerson busch
Nov 15 '18 at 5:20
if like that. is it call EnumProcesses twice. it make execution slow?
– Dwerson busch
Nov 15 '18 at 5:20
You have no other choice if you don't pass an array that is big enough the first time you call
EnumProcesses().– Swordfish
Nov 15 '18 at 5:44
You have no other choice if you don't pass an array that is big enough the first time you call
EnumProcesses().– Swordfish
Nov 15 '18 at 5:44
add a comment |
0
A vector isn't a pointer to DWORD; however, this vector happens to contain one so you can
if (!EnumProcesses(aProcesses.data(), aProcesses.capacity(), &cbNeeded))
if your compiler is compiling for the C++11 Standard revision or more recent or
if (!EnumProcesses(&aProcesses[0], aProcesses.capacity(), &cbNeeded))
if it is not.
But that just gets things compiling
There are logic problems yet to be dealt with.
const int MAX_PROCESSES = 1024; // very few Windows systems will exceed 1024 processes
std::vector<DWORD> aProcesses(MAX_PROCESSES); // allocate space
DWORD cbNeeded;
if (!EnumProcesses(aProcesses.data(),
aProcesses.capacity() * sizeof(DWORD), // size in bytes, not elements
&cbNeeded))
{
return 1;
}
//for (auto& p : aProcesses) Not all processes may have been filled. The unused portions
//are zeroed, so this is safe, but wasteful
for (int i = 0; i < cbNeeded / sizeof(DWORD); ++i)
{
std::cout << aProcesses[i] << std::endl;
}
answered Nov 15 '18 at 4:51
user4581301user4581301
20.5k51931
is not MAX_NUM_DWORDS macro manually allocated memory? i should knows max possible the value?
– Dwerson busch
Nov 15 '18 at 5:06
@Dwersonbusch No, that was a stub. There is pretty much no way to know how many processes are running, but this rarely gets above a few hundred on all but the busiest of servers. Will update question.
– user4581301
Nov 15 '18 at 5:12
EnumProcesses api it just example. i knows if max processes will not run above 1k. but there's other winapi it will return above 1k value.
– Dwerson busch
Nov 15 '18 at 5:18
Why do you say that&aProcesses[0]isn't legal?aProcesses[0]returns a reference,T&, and taking the address of a reference is just a pointer to the referenced object. A DWORD in this case.
– doug
Nov 15 '18 at 5:58
@doug I can't imagine how you could dovectorand theoverload so that&vec[0]won't work, but it's not guaranteed. It's only an issue with C++ 98 and 03, so I did some old school standard diving and in 2005 drafts the wording looks like obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size(). Looks pretty conclusive that it ought to work and I'm gonna have to stop. It's too damn late and I work in the morning. And I'm having trouble typing work. Always a bad sign.
– user4581301
Nov 15 '18 at 6:59
add a comment |
0
A vector isn't a pointer to DWORD; however, this vector happens to contain one so you can
if (!EnumProcesses(aProcesses.data(), aProcesses.capacity(), &cbNeeded))
if your compiler is compiling for the C++11 Standard revision or more recent or
if (!EnumProcesses(&aProcesses[0], aProcesses.capacity(), &cbNeeded))
if it is not.
But that just gets things compiling
There are logic problems yet to be dealt with.
const int MAX_PROCESSES = 1024; // very few Windows systems will exceed 1024 processes
std::vector<DWORD> aProcesses(MAX_PROCESSES); // allocate space
DWORD cbNeeded;
if (!EnumProcesses(aProcesses.data(),
aProcesses.capacity() * sizeof(DWORD), // size in bytes, not elements
&cbNeeded))
{
return 1;
}
//for (auto& p : aProcesses) Not all processes may have been filled. The unused portions
//are zeroed, so this is safe, but wasteful
for (int i = 0; i < cbNeeded / sizeof(DWORD); ++i)
{
std::cout << aProcesses[i] << std::endl;
}
answered Nov 15 '18 at 4:51
user4581301user4581301
20.5k51931
is not MAX_NUM_DWORDS macro manually allocated memory? i should knows max possible the value?
– Dwerson busch
Nov 15 '18 at 5:06
@Dwersonbusch No, that was a stub. There is pretty much no way to know how many processes are running, but this rarely gets above a few hundred on all but the busiest of servers. Will update question.
– user4581301
Nov 15 '18 at 5:12
EnumProcesses api it just example. i knows if max processes will not run above 1k. but there's other winapi it will return above 1k value.
– Dwerson busch
Nov 15 '18 at 5:18
Why do you say that&aProcesses[0]isn't legal?aProcesses[0]returns a reference,T&, and taking the address of a reference is just a pointer to the referenced object. A DWORD in this case.
– doug
Nov 15 '18 at 5:58
@doug I can't imagine how you could dovectorand theoverload so that&vec[0]won't work, but it's not guaranteed. It's only an issue with C++ 98 and 03, so I did some old school standard diving and in 2005 drafts the wording looks like obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size(). Looks pretty conclusive that it ought to work and I'm gonna have to stop. It's too damn late and I work in the morning. And I'm having trouble typing work. Always a bad sign.
– user4581301
Nov 15 '18 at 6:59
add a comment |
0
0
0
A vector isn't a pointer to DWORD; however, this vector happens to contain one so you can
if (!EnumProcesses(aProcesses.data(), aProcesses.capacity(), &cbNeeded))
if your compiler is compiling for the C++11 Standard revision or more recent or
if (!EnumProcesses(&aProcesses[0], aProcesses.capacity(), &cbNeeded))
if it is not.
But that just gets things compiling
There are logic problems yet to be dealt with.
const int MAX_PROCESSES = 1024; // very few Windows systems will exceed 1024 processes
std::vector<DWORD> aProcesses(MAX_PROCESSES); // allocate space
DWORD cbNeeded;
if (!EnumProcesses(aProcesses.data(),
aProcesses.capacity() * sizeof(DWORD), // size in bytes, not elements
&cbNeeded))
{
return 1;
}
//for (auto& p : aProcesses) Not all processes may have been filled. The unused portions
//are zeroed, so this is safe, but wasteful
for (int i = 0; i < cbNeeded / sizeof(DWORD); ++i)
{
std::cout << aProcesses[i] << std::endl;
}
answered Nov 15 '18 at 4:51
user4581301user4581301
20.5k51931
A vector isn't a pointer to DWORD; however, this vector happens to contain one so you can
if (!EnumProcesses(aProcesses.data(), aProcesses.capacity(), &cbNeeded))
if your compiler is compiling for the C++11 Standard revision or more recent or
if (!EnumProcesses(&aProcesses[0], aProcesses.capacity(), &cbNeeded))
if it is not.
But that just gets things compiling
There are logic problems yet to be dealt with.
const int MAX_PROCESSES = 1024; // very few Windows systems will exceed 1024 processes
std::vector<DWORD> aProcesses(MAX_PROCESSES); // allocate space
DWORD cbNeeded;
if (!EnumProcesses(aProcesses.data(),
aProcesses.capacity() * sizeof(DWORD), // size in bytes, not elements
&cbNeeded))
{
return 1;
}
//for (auto& p : aProcesses) Not all processes may have been filled. The unused portions
//are zeroed, so this is safe, but wasteful
for (int i = 0; i < cbNeeded / sizeof(DWORD); ++i)
{
std::cout << aProcesses[i] << std::endl;
}
answered Nov 15 '18 at 4:51
user4581301user4581301
20.5k51931
edited Nov 15 '18 at 7:00
answered Nov 15 '18 at 4:51
user4581301user4581301
20.5k51931
answered Nov 15 '18 at 4:51
user4581301user4581301
20.5k51931
answered Nov 15 '18 at 4:51
user4581301user4581301
20.5k51931
20.5k51931
is not MAX_NUM_DWORDS macro manually allocated memory? i should knows max possible the value?
– Dwerson busch
Nov 15 '18 at 5:06
@Dwersonbusch No, that was a stub. There is pretty much no way to know how many processes are running, but this rarely gets above a few hundred on all but the busiest of servers. Will update question.
– user4581301
Nov 15 '18 at 5:12
EnumProcesses api it just example. i knows if max processes will not run above 1k. but there's other winapi it will return above 1k value.
– Dwerson busch
Nov 15 '18 at 5:18
Why do you say that&aProcesses[0]isn't legal?aProcesses[0]returns a reference,T&, and taking the address of a reference is just a pointer to the referenced object. A DWORD in this case.
– doug
Nov 15 '18 at 5:58
@doug I can't imagine how you could dovectorand theoverload so that&vec[0]won't work, but it's not guaranteed. It's only an issue with C++ 98 and 03, so I did some old school standard diving and in 2005 drafts the wording looks like obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size(). Looks pretty conclusive that it ought to work and I'm gonna have to stop. It's too damn late and I work in the morning. And I'm having trouble typing work. Always a bad sign.
– user4581301
Nov 15 '18 at 6:59
add a comment |
is not MAX_NUM_DWORDS macro manually allocated memory? i should knows max possible the value?
– Dwerson busch
Nov 15 '18 at 5:06
@Dwersonbusch No, that was a stub. There is pretty much no way to know how many processes are running, but this rarely gets above a few hundred on all but the busiest of servers. Will update question.
– user4581301
Nov 15 '18 at 5:12
EnumProcesses api it just example. i knows if max processes will not run above 1k. but there's other winapi it will return above 1k value.
– Dwerson busch
Nov 15 '18 at 5:18
Why do you say that&aProcesses[0]isn't legal?aProcesses[0]returns a reference,T&, and taking the address of a reference is just a pointer to the referenced object. A DWORD in this case.
– doug
Nov 15 '18 at 5:58
@doug I can't imagine how you could dovectorand theoverload so that&vec[0]won't work, but it's not guaranteed. It's only an issue with C++ 98 and 03, so I did some old school standard diving and in 2005 drafts the wording looks like obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size(). Looks pretty conclusive that it ought to work and I'm gonna have to stop. It's too damn late and I work in the morning. And I'm having trouble typing work. Always a bad sign.
– user4581301
Nov 15 '18 at 6:59
is not MAX_NUM_DWORDS macro manually allocated memory? i should knows max possible the value?
– Dwerson busch
Nov 15 '18 at 5:06
is not MAX_NUM_DWORDS macro manually allocated memory? i should knows max possible the value?
– Dwerson busch
Nov 15 '18 at 5:06
@Dwersonbusch No, that was a stub. There is pretty much no way to know how many processes are running, but this rarely gets above a few hundred on all but the busiest of servers. Will update question.
– user4581301
Nov 15 '18 at 5:12
@Dwersonbusch No, that was a stub. There is pretty much no way to know how many processes are running, but this rarely gets above a few hundred on all but the busiest of servers. Will update question.
– user4581301
Nov 15 '18 at 5:12
EnumProcesses api it just example. i knows if max processes will not run above 1k. but there's other winapi it will return above 1k value.
– Dwerson busch
Nov 15 '18 at 5:18
EnumProcesses api it just example. i knows if max processes will not run above 1k. but there's other winapi it will return above 1k value.
– Dwerson busch
Nov 15 '18 at 5:18
Why do you say that
&aProcesses[0] isn't legal? aProcesses[0] returns a reference, T&, and taking the address of a reference is just a pointer to the referenced object. A DWORD in this case.– doug
Nov 15 '18 at 5:58
Why do you say that
&aProcesses[0] isn't legal? aProcesses[0] returns a reference, T&, and taking the address of a reference is just a pointer to the referenced object. A DWORD in this case.– doug
Nov 15 '18 at 5:58
@doug I can't imagine how you could do
vector and the &vec[0] won't work, but it's not guaranteed. It's only an issue with C++ 98 and 03, so I did some old school standard diving and in 2005 drafts the wording looks like obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size(). Looks pretty conclusive that it ought to work and I'm gonna have to stop. It's too damn late and I work in the morning. And I'm having trouble typing work. Always a bad sign.– user4581301
Nov 15 '18 at 6:59
@doug I can't imagine how you could do
vector and the &vec[0] won't work, but it's not guaranteed. It's only an issue with C++ 98 and 03, so I did some old school standard diving and in 2005 drafts the wording looks like obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size(). Looks pretty conclusive that it ought to work and I'm gonna have to stop. It's too damn late and I work in the morning. And I'm having trouble typing work. Always a bad sign.– user4581301
Nov 15 '18 at 6:59
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2
instead of aProcesses` use
aProcesses.data()or alternately&aProcesses[0]see: en.cppreference.com/w/cpp/container/vector/data– doug
Nov 15 '18 at 4:48
1
Note that you need to call
resize()on the vector yourself before passing a pointer to the data buffer to an API function, since Windows doesn't know anything about c++.– Jonathan Potter
Nov 15 '18 at 4:51
It would be helpful to include the code you anticipate replacing to provide more specific advice.
– doug
Nov 15 '18 at 4:58
@doug i include manual allocate memory ways
– Dwerson busch
Nov 15 '18 at 5:04
Just declare your vector like so:
std::vector<DWORD> aProcesses(1024);and useaProcesses.data()which is a pointer to the first vector element.– doug
Nov 15 '18 at 5:08