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  • How to overload operator<< for qDebug

    - by iyo
    Hi, I'm trying to create more useful debug messages for my class where store data. My code is looking something like this #include <QAbstractTableModel> #include <QDebug> /** * Model for storing data. */ class DataModel : public QAbstractTableModel { // for debugging purposes friend QDebug & operator<< (const QDebug &d, DataModel model); //other stuff }; /** * Overloading operator for debugging purposes */ QDebug & operator<< (QDebug &d, DataModel model) { d << "Hello world!"; return d; } I expect qDebug() << model will print "Hello world!". However, there is alway something like "QAbstractTableModel(0x1c7e520)" on the output. Do you have any idea what's wrong?

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  • LPCSTR, TCHAR, String

    - by user285327
    I am use next type of strings: LPCSTR, TCHAR, String i want to convert: 1) from TCHAR to LPCSTR 2) from String to char I convert from TCHAR to LPCSTR by that code: RunPath = TEXT("C:\\1"); LPCSTR Path = (LPCSTR)RunPath; From String to char i convert by that code: SaveFileDialog^ saveFileDialog1 = gcnew SaveFileDialog; saveFileDialog1->Title = "?????????? ?????-????????"; saveFileDialog1->Filter = "bck files (*.bck)|*.bck"; saveFileDialog1->RestoreDirectory = true; pin_ptr<const wchar_t> wch = TEXT(""); if ( saveFileDialog1->ShowDialog() == System::Windows::Forms::DialogResult::OK ) { wch = PtrToStringChars(saveFileDialog1->FileName); } else return; ofstream os(wch, ios::binary); My problem is that when i set "Configuration Properties - General Character Set in "Use Multi-Byte Character Set" the first part of code work correctly. But the second part of code return error C2440. When i set "Configuration Properties - General Character Set in "Use Unicode" the second part of code work correctly. But the first part of code return the only first character from TCHAR to LPCSTR.

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  • Boost class/struct serialization to byte array

    - by Dave18
    does boost library provide functions to pack the class/struct data into a byte array to shorten the length of serialized data? Currently i'm using stringstream to get the serialized data, for example - struct data { std::string s1; std::string s2; int i; }; template <typename Archive> void serialize(Archive &ar, data &d, const unsigned int version) { ar & d.s1; ar & d.s2; ar & d.i; } int main() { data d; d.s1 = "This is my first string"; d.s2 = "This is my second string"; d.i = 10000; std::stringstream archive_stream; boost::archive::text_oarchive archive(archive_stream); archive.operator <<(d); } How would i use a byte array instead of stringstream for data?

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  • Populate struct values with function argument

    - by adohertyd
    I am working on a program and part of it requires me to create a struct called DETAILS with the fields name, age, and height. I want to populate the record with data using a function argument. When I run my code I get compiler errors. I have put the errors in comment form beside the lines it is returned for but I can't fix them. Really could do with some help here guys thanks so much. Here is my code: #include <cstdlib> #include <iostream> #include <iomanip> using namespace std; const int LEN=100; struct DETAILS { char name[LEN]; int age; double height; }; person fillperson(struct DETAILS, char[LEN], int, double); int main() { struct person David; fillperson(David, "David Greene", 38, 180.0); //deprecated conversion from string constant to char * [-Wwrite-Strings] } person fillperson(struct DETAILS, char[LEN] name, int age, double height) //expected , or ... before 'name' { cin>>David.name>>name; cin>>David.age>>age; cin>>David.height>>height; cout<<"Done"<<endl; }

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  • SFINAE failing with enum template parameter

    - by zeroes00
    Can someone explain the following behaviour (I'm using Visual Studio 2010). header: #pragma once #include <boost\utility\enable_if.hpp> using boost::enable_if_c; enum WeekDay {MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY}; template<WeekDay DAY> typename enable_if_c< DAY==SUNDAY, bool >::type goToWork() {return false;} template<WeekDay DAY> typename enable_if_c< DAY!=SUNDAY, bool >::type goToWork() {return true;} source: bool b = goToWork<MONDAY>(); compiler this gives error C2770: invalid explicit template argument(s) for 'enable_if_c<DAY!=6,bool>::type goToWork(void)' and error C2770: invalid explicit template argument(s) for 'enable_if_c<DAY==6,bool>::type goToWork(void)' But if I change the function template parameter from the enum type WeekDay to int, it compiles fine: template<int DAY> typename enable_if_c< DAY==SUNDAY, bool >::type goToWork() {return false;} template<int DAY> typename enable_if_c< DAY!=SUNDAY, bool >::type goToWork() {return true;} Also the normal function template specialization works fine, no surprises there: template<WeekDay DAY> bool goToWork() {return true;} template<> bool goToWork<SUNDAY>() {return false;} To make things even weirder, if I change the source file to use any other WeekDay than MONDAY or TUESDAY, i.e. bool b = goToWork<THURSDAY>(); the error changes to this: error C2440: 'specialization' : cannot convert from 'int' to 'const WeekDay' Conversion to enumeration type requires an explicit cast (static_cast, C-style cast or function-style cast)

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  • Finding missing symbols in libstd++ on Debian/squeeze

    - by Florian Le Goff
    I'm trying to use a pre-compiled library provided as a .so file. This file is dynamically linked against a few librairies : $ ldd /usr/local/test/lib/libtest.so linux-gate.so.1 = (0xb770d000) libstdc++-libc6.1-1.so.2 = not found libm.so.6 = /lib/i686/cmov/libm.so.6 (0xb75e1000) libc.so.6 = /lib/i686/cmov/libc.so.6 (0xb7499000) /lib/ld-linux.so.2 (0xb770e000) libgcc_s.so.1 = /lib/libgcc_s.so.1 (0xb747c000) Unfortunately, in Debian/squeeze, there is no libstdc++-libc6.1-1.so.* file. Only a libstdc++.so.* file provided by the libstdc++6 package. I tried to link (using ln -s) libstdc++-libc6.1-1.so.2 to the libstdc++.so.6 file. It does not work, a batch of symbols seems to be lacking when I'm trying to ld my .o files with this lib. /usr/local/test/lib/libtest.so: undefined reference to `__builtin_vec_delete' /usr/local/test/lib/libtest.so: undefined reference to `istrstream::istrstream(int, char const *, int)' /usr/local/test/lib/libtest.so: undefined reference to `__rtti_user' /usr/local/test/lib/libtest.so: undefined reference to `__builtin_new' /usr/local/test/lib/libtest.so: undefined reference to `istream::ignore(int, int)' What would you do ? How may I find in which lib those symbols are exported ?

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  • Valgrind says "stack allocation," I say "heap allocation"

    - by Joel J. Adamson
    Dear Friends, I am trying to trace a segfault with valgrind. I get the following message from valgrind: ==3683== Conditional jump or move depends on uninitialised value(s) ==3683== at 0x4C277C5: sparse_mat_mat_kron (sparse.c:165) ==3683== by 0x4C2706E: rec_mating (rec.c:176) ==3683== by 0x401C1C: age_dep_iterate (age_dep.c:287) ==3683== by 0x4014CB: main (age_dep.c:92) ==3683== Uninitialised value was created by a stack allocation ==3683== at 0x401848: age_dep_init_params (age_dep.c:131) ==3683== ==3683== Conditional jump or move depends on uninitialised value(s) ==3683== at 0x4C277C7: sparse_mat_mat_kron (sparse.c:165) ==3683== by 0x4C2706E: rec_mating (rec.c:176) ==3683== by 0x401C1C: age_dep_iterate (age_dep.c:287) ==3683== by 0x4014CB: main (age_dep.c:92) ==3683== Uninitialised value was created by a stack allocation ==3683== at 0x401848: age_dep_init_params (age_dep.c:131) However, here's the offending line: /* allocate mating table */ age_dep_data->mtable = malloc (age_dep_data->geno * sizeof (double *)); if (age_dep_data->mtable == NULL) error (ENOMEM, ENOMEM, nullmsg, __LINE__); for (int j = 0; j < age_dep_data->geno; j++) { 131=> age_dep_data->mtable[j] = calloc (age_dep_data->geno, sizeof (double)); if (age_dep_data->mtable[j] == NULL) error (ENOMEM, ENOMEM, nullmsg, __LINE__); } What gives? I thought any call to malloc or calloc allocated heap space; there is no other variable allocated here, right? Is it possible there's another allocation going on (the offending stack allocation) that I'm not seeing? You asked to see the code, here goes: /* Copyright 2010 Joel J. Adamson <[email protected]> $Id: age_dep.c 1010 2010-04-21 19:19:16Z joel $ age_dep.c:main file Joel J. Adamson -- http://www.unc.edu/~adamsonj Servedio Lab University of North Carolina at Chapel Hill CB #3280, Coker Hall Chapel Hill, NC 27599-3280 This file is part of an investigation of age-dependent sexual selection. This code is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with haploid. If not, see <http://www.gnu.org/licenses/>. */ #include "age_dep.h" /* global variables */ extern struct argp age_dep_argp; /* global error message variables */ char * nullmsg = "Null pointer: %i"; /* error message for conversions: */ char * errmsg = "Representation error: %s"; /* precision for formatted output: */ const char prec[] = "%-#9.8f "; const size_t age_max = AGEMAX; /* maximum age of males */ static int keep_going_p = 1; int main (int argc, char ** argv) { /* often used counters: */ int i, j; /* read the command line */ struct age_dep_args age_dep_args = { NULL, NULL, NULL }; argp_parse (&age_dep_argp, argc, argv, 0, 0, &age_dep_args); /* set the parameters here: */ /* initialize an age_dep_params structure, set the members */ age_dep_params_t * params = malloc (sizeof (age_dep_params_t)); if (params == NULL) error (ENOMEM, ENOMEM, nullmsg, __LINE__); age_dep_init_params (params, &age_dep_args); /* initialize frequencies: this initializes a list of pointers to initial frqeuencies, terminated by a NULL pointer*/ params->freqs = age_dep_init (&age_dep_args); params->by = 0.0; /* what range of parameters do we want, and with what stepsize? */ /* we should go from 0 to half-of-theta with a step size of about 0.01 */ double from = 0.0; double to = params->theta / 2.0; double stepsz = 0.01; /* did you think I would spell the whole word? */ unsigned int numparts = floor(to / stepsz); do { #pragma omp parallel for private(i) firstprivate(params) \ shared(stepsz, numparts) for (i = 0; i < numparts; i++) { params->by = i * stepsz; int tries = 0; while (keep_going_p) { /* each time through, modify mfreqs and mating table, then go again */ keep_going_p = age_dep_iterate (params, ++tries); if (keep_going_p == ERANGE) error (ERANGE, ERANGE, "Failure to converge\n"); } fprintf (stdout, "%i iterations\n", tries); } /* for i < numparts */ params->freqs = params->freqs->next; } while (params->freqs->next != NULL); return 0; } inline double age_dep_pmate (double age_dep_t, unsigned int genot, double bp, double ba) { /* the probability of mating between these phenotypes */ /* the female preference depends on whether the female has the preference allele, the strength of preference (parameter bp) and the male phenotype (age_dep_t); if the female lacks the preference allele, then this will return 0, which is not quite accurate; it should return 1 */ return bits_isset (genot, CLOCI)? 1.0 - exp (-bp * age_dep_t) + ba: 1.0; } inline double age_dep_trait (int age, unsigned int genot, double by) { /* return the male trait, a function of the trait locus, age, the age-dependent scaling parameter (bx) and the males condition genotype */ double C; double T; /* get the male's condition genotype */ C = (double) bits_popcount (bits_extract (0, CLOCI, genot)); /* get his trait genotype */ T = bits_isset (genot, CLOCI + 1)? 1.0: 0.0; /* return the trait value */ return T * by * exp (age * C); } int age_dep_iterate (age_dep_params_t * data, unsigned int tries) { /* main driver routine */ /* number of bytes for female frequencies */ size_t geno = data->age_dep_data->geno; size_t genosize = geno * sizeof (double); /* female frequencies are equal to male frequencies at birth (before selection) */ double ffreqs[geno]; if (ffreqs == NULL) error (ENOMEM, ENOMEM, nullmsg, __LINE__); /* do not set! Use memcpy (we need to alter male frequencies (selection) without altering female frequencies) */ memmove (ffreqs, data->freqs->freqs[0], genosize); /* for (int i = 0; i < geno; i++) */ /* ffreqs[i] = data->freqs->freqs[0][i]; */ #ifdef PRMTABLE age_dep_pr_mfreqs (data); #endif /* PRMTABLE */ /* natural selection: */ age_dep_ns (data); /* normalized mating table with new frequencies */ age_dep_norm_mtable (ffreqs, data); #ifdef PRMTABLE age_dep_pr_mtable (data); #endif /* PRMTABLE */ double * newfreqs; /* mutate here */ /* i.e. get the new frequency of 0-year-olds using recombination; */ newfreqs = rec_mating (data->age_dep_data); /* return block */ { if (sim_stop_ck (data->freqs->freqs[0], newfreqs, GENO, TOL) == 0) { /* if we have converged, stop the iterations and handle the data */ age_dep_sim_out (data, stdout); return 0; } else if (tries > MAXTRIES) return ERANGE; else { /* advance generations */ for (int j = age_max - 1; j < 0; j--) memmove (data->freqs->freqs[j], data->freqs->freqs[j-1], genosize); /* advance the first age-class */ memmove (data->freqs->freqs[0], newfreqs, genosize); return 1; } } } void age_dep_ns (age_dep_params_t * data) { /* calculate the new frequency of genotypes given additive fitness and selection coefficient s */ size_t geno = data->age_dep_data->geno; double w[geno]; double wbar, dtheta, ttheta, dcond, tcond; double t, cond; /* fitness parameters */ double mu, nu; mu = data->wparams[0]; nu = data->wparams[1]; /* calculate fitness */ for (int j = 0; j < age_max; j++) { int i; for (i = 0; i < geno; i++) { /* calculate male trait: */ t = age_dep_trait(j, i, data->by); /* calculate condition: */ cond = (double) bits_popcount (bits_extract(0, CLOCI, i)); /* trait-based fitness term */ dtheta = data->theta - t; ttheta = (dtheta * dtheta) / (2.0 * nu * nu); /* condition-based fitness term */ dcond = CLOCI - cond; tcond = (dcond * dcond) / (2.0 * mu * mu); /* calculate male fitness */ w[i] = 1 + exp(-tcond) - exp(-ttheta); } /* calculate mean fitness */ /* as long as we calculate wbar before altering any values of freqs[], we're safe */ wbar = gen_mean (data->freqs->freqs[j], w, geno); for (i = 0; i < geno; i++) data->freqs->freqs[j][i] = (data->freqs->freqs[j][i] * w[i]) / wbar; } } void age_dep_norm_mtable (double * ffreqs, age_dep_params_t * params) { /* this function produces a single mating table that forms the input for recombination () */ /* i is female genotype; j is male genotype; k is male age */ int i,j,k; double norm_denom; double trait; size_t geno = params->age_dep_data->geno; for (i = 0; i < geno; i++) { double norm_mtable[geno]; /* initialize the denominator: */ norm_denom = 0.0; /* find the probability of mating and add it to the denominator */ for (j = 0; j < geno; j++) { /* initialize entry: */ norm_mtable[j] = 0.0; for (k = 0; k < age_max; k++) { trait = age_dep_trait (k, j, params->by); norm_mtable[j] += age_dep_pmate (trait, i, params->bp, params->ba) * (params->freqs->freqs)[k][j]; } norm_denom += norm_mtable[j]; } /* now calculate entry (i,j) */ for (j = 0; j < geno; j++) params->age_dep_data->mtable[i][j] = (ffreqs[i] * norm_mtable[j]) / norm_denom; } } My current suspicion is the array newfreqs: I can't memmove, memcpy or assign a stack variable then hope it will persist, can I? rec_mating() returns double *.

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  • string Comparison

    - by muhammad-aslam
    I want to compare two user input strings, but not able to do so... #include "stdafx.h" #include "iostream" #include "string" using namespace std; int _tmain(int argc, _TCHAR* argv0[]) { string my_string; string my_string2; cout<<"Enter string"<<endl; cin>>my_string; cout<<"Enter 2nd string"<<endl; cin>>my_string2; cout<<my_string<<" "<<my_string2; strcmp(my_string,my_string2); int result; result= strcmp(my_string,my_string2); cout<<result<<endl; return 0; } This error is appearing. Error 1 error C2664: 'strcmp' : cannot convert parameter 1 from 'std::string' to 'const char *' c:\users\asad\documents\visual studio 2008\projects\string\string\string.cpp 23 String

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  • stat() get group name is root

    - by mengmenger
    I have a file src.tar.gz whoes owner and group are named "src". When I run test.c compiled with name "test" (permission: -rwsr-xr-x owner:root group:staff) The way I run it: I am running it as group member under "src" group. But I run "test" as root since "test" permission is -rwsr-xr-x Question: Why did result come out like this? is the src.tar.gz group should be "src"? Output: Error: my group: src Error: src.tar.gz group is root test.c #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <string.h> #include <sys/types.h> #include <sys/stat.h> #include <grp.h> void main(int ac, char **args) { const char *ERR_MSG_FORMAT = "%s: %s %s.\n"; char *ptr_source_file = "src.tar.gz"; struct stat src_stat; gid_t src_gid, my_gid; int i = stat(ptr_source_file, &src_stat); my_gid = getgid(); struct group *cur_gr = getgrgid(my_gid); fprintf(stderr, ERR_MSG_FORMAT, "Error", "my group: ", cur_gr->gr_name); src_gid = src_stat.st_gid; struct group *src_gr = getgrgid(src_gid); fprintf(stderr, ERR_MSG_FORMAT, "Error","src.tar.gz group is ", src_gr->gr_name); }

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  • Creating and using a static lib in xcode

    - by Alasdair Morrison
    I am trying to create a static library in xcode and link to that static library from another program. So as a test i have created a BSD static C library project and just added the following code: //Test.h int testFunction(); //Test.cpp #include "Test.h" int testFunction() { return 12; } This compiles fine and create a .a file (libTest.a). Now i want to use it in another program so I create a new xcode project (cocoa application) Have the following code: //main.cpp #include <iostream> #include "Testlib.h" int main (int argc, char * const argv[]) { // insert code here... std::cout << "Result:\n" <<testFunction(); return 0; } //Testlib.h extern int testFunction(); I right clicked on the project - add - existing framework - add other Selected the .a file and it added it into the project view. I always get this linker error: Build TestUselibrary of project TestUselibrary with configuration Debug Ld build/Debug/TestUselibrary normal x86_64 cd /Users/myname/location/TestUselibrary setenv MACOSX_DEPLOYMENT_TARGET 10.6 /Developer/usr/bin/g++-4.2 -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk -L/Users/myname/location/TestUselibrary/build/Debug -L/Users/myname/location/TestUselibrary/../Test/build/Debug -F/Users/myname/location/TestUselibrary/build/Debug -filelist /Users/myname/location/TestUselibrary/build/TestUselibrary.build/Debug/TestUselibrary.build/Objects-normal/x86_64/TestUselibrary.LinkFileList -mmacosx-version-min=10.6 -lTest -o /Users/myname/location/TestUselibrary/build/Debug/TestUselibrary Undefined symbols: "testFunction()", referenced from: _main in main.o ld: symbol(s) not found collect2: ld returned 1 exit status I am new to macosx development and fairly new to c++. I am probably missing something fairly obvious, all my experience comes from creating dlls on the windows platform. I really appreciate any help.

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  • Enumerating a string

    - by JamesB
    I have a status which is stored as a string of a set length, either in a file or a database. I'm looking to enumerate the possible status' I have the following type to define the possible status' Type TStatus = (fsNormal = Ord('N'),fsEditedOnScreen = Ord('O'), fsMissing = Ord('M'),fsEstimated = Ord('E'),fsSuspect = Ord('s'), fsSuspectFromOnScreen = Ord('o'),fsSuspectMissing = Ord('m'), fsSuspectEstimated = Ord('e')); Firstly is this really a good idea? or should I have a seperate const array storing the char conversions? That would mean more than one place to update. Now convert a string to a status array I have the following, but how can I check if a char is valid without looping through the enumeration? Function StrToStatus(Value : String):TStatusArray; var i: Integer; begin if Trim(Value) = '' then begin SetLength(Result,0); Exit; end; SetLength(Result,Length(Value)); for i := 1 to Length(Value) do begin Result[i] := TStatus(Value[i]); // I don't think this line is safe. end; end; AFAIK this should be fine for converting back again. Function StatusToStr(Value : TStatusArray):String; var i: Integer; begin for i := 0 to Length(Value) - 1 do Result := Result + Chr(Ord(Value[i])) end; I'm using Delphi 2007

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  • Disable Painting of the VScrollbar in a System.Windows.Forms.RichTextBox

    - by SchlaWiener
    I have a custom control inherited from RichTextBox. This control has the ability to "disable" rich text editing. I achive this by just setting the Rtf property to the text property during the TextChanged event. this is how my code looks like: private bool lockTextChanged; void RichTextBox_TextChanged(object sender, EventArgs e) { // prevent StackOverflowException if (lockTextChanged) return; // remember current position int rtbstart = rtb.SelectionStart; int len = rtb.SelectionLength; // prevent painting rtb.SuspendLayout(); // set the text property to remove the entire formatting. lockTextChanged = true; rtb.Text = rtb.Text; rtb.Select(rtbstart, len); lockTextChanged = false; rtb.ResumeLayout(true); } That worked well. However in a large text with like 200 lines the controls jitters (you see the first lines of text for the wink). To prevent that from happening I filter the WM_PAINT between SuspendLayout() and ResumeLayout() private bool layoutSuspended; public new void SuspendLayout() { layoutSuspended = true; base.SuspendLayout(); } public new void ResumeLayout() { layoutSuspended = false; base.ResumeLayout(); } public new void ResumeLayout(bool performLayout) { layoutSuspended = false; base.ResumeLayout(performLayout); } private const int WM_PAINT = 0x000F; protected override void WndProc(ref System.Windows.Forms.Message m) { if (!(m.Msg == WM_PAINT && layoutSuspended)) base.WndProc(ref m); } that did the trick, the RichTextBox isn't jittering anymoe. That's what I wanted to achive, except one thing: The scrollbar is still jittering everytime I type text to my control. Now my question: Does anyone have a clue for me how to prevent the scrollbar from redrawing during Suspend/Resume Layout?

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  • event.clientX is readonly?

    - by Duracell
    Working in IE 8, mostly, but trying to write a portable solution for modern browsers. Using telerik controls. I'm catching the 'Showing' client-side event of the RadContextMenu and trying to adjust it's coordinates. The clientX, clientY and x,y members of the DOM event cannot be assigned a new value. Visual Studio breaks with a "htmlfile: Member not found" error. My goal is to get a RadContextMenu to show inside a RadEditor when the user clicks in it (under certain conditions, this is a requirement from management). So I capture the onclick event for the RadEditor's content area (radEditor.get_document().body;). I then call show(evt) on the context menu, where 'evt' is the event object corresponding to the click event. Because the RadEditor's content is in an IFRAME, you have to adjust the position of the click event before the context menu displays. This is done in the "Showing" event. However, I cannot assign a value to the members .clientX and friends. It's as if javascript has temporarily forgotten about integer + and += operators. Is it possible that these members have become readonly/const at some point? var evt = args.get_domEvent(); while (node) { evt.clientX += node.offsetLeft; //'Member not found' here. evt.clientY += node.offsetTop; node = node.offsetParent; } evt.clientY += sender.get_element().clientHeight;

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  • Why did this work with Visual C++, but not with gcc?

    - by Carlos Nunez
    I've been working on a senior project for the last several months now, and a major sticking point in our team's development process has been dealing wtih rifts between Visual-C++ and gcc. (Yes, I know we all should have had the same development environment.) Things are about finished up at this point, but I ran into a moderate bug just today that had me wondering whether Visual-C++ is easier on newbies (like me) by design. In one of my headers, there is a function that relies on strtok to chop up a string, do some comparisons and return a string with a similar format. It works a little something like the following: int main() { string a, b, c; //Do stuff with a and b. c = get_string(a,b); } string get_string(string a, string b) { const char * a_ch, b_ch; a_ch = strtok(a.c_str(),","); b_ch = strtok(b.c_str(),","); } strtok is infamous for being great at tokenizing, but equally great at destroying the original string to be tokenized. Thus, when I compiled this with gcc and tried to do anything with a or b, I got unexpected behavior, since the separator used was completely removed in the string. Here's an example in case I'm unclear; if I set a = "Jim,Bob,Mary" and b="Grace,Soo,Hyun", they would be defined as a="JimBobMary" and b="GraceSooHyun" instead of staying the same like I wanted. However, when I compiled this under Visual C++, I got back the original strings and the program executed fine. I tried dynamically allocating memory to the strings and copying them the "standard" way, but the only way that worked was using malloc() and free(), which I hear is discouraged in C++. While I'm curious about that, the real question I have is this: Why did the program work when compiled in VC++, but not with gcc? (This is one of many conflicts that I experienced while trying to make the code cross-platform.) Thanks in advance! -Carlos Nunez

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  • malloc works, cudaHostAlloc segfaults?

    - by Mikhail
    I am new to CUDA and I want to use cudaHostAlloc. I was able to isolate my problem to this following code. Using malloc for host allocation works, using cudaHostAlloc results in a segfault, possibly because the area allocated is invalid? When I dump the pointer in both cases it is not null, so cudaHostAlloc returns something... works in_h = (int*) malloc(length*sizeof(int)); //works for (int i = 0;i<length;i++) in_h[i]=2; doesn't work cudaHostAlloc((void**)&in_h,length*sizeof(int),cudaHostAllocDefault); for (int i = 0;i<length;i++) in_h[i]=2; //segfaults Standalone Code #include <stdio.h> void checkDevice() { cudaDeviceProp info; int deviceName; cudaGetDevice(&deviceName); cudaGetDeviceProperties(&info,deviceName); if (!info.deviceOverlap) { printf("Compute device can't use streams and should be discared."); exit(EXIT_FAILURE); } } int main() { checkDevice(); int *in_h; const int length = 10000; cudaHostAlloc((void**)&in_h,length*sizeof(int),cudaHostAllocDefault); printf("segfault comming %d\n",in_h); for (int i = 0;i<length;i++) { in_h[i]=2; } free(in_h); return EXIT_SUCCESS; } ~ Invocation [id129]$ nvcc fun.cu [id129]$ ./a.out segfault comming 327641824 Segmentation fault (core dumped) Details Program is run in interactive mode on a cluster. I was told that an invocation of the program from the compute node pushes it to the cluster. Have not had any trouble with other home made toy cuda codes.

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  • Linking error while using Qt static built libraries

    - by Kamran Amini
    I hope this is not a duplicate. Recently I'm developing a native C++ application using Qt 4.8.3 and VS2008. Since clients run the application on their naked machines, they need to install VC++ 2008 Redistribution package. So I decided to make it statically linked. I changed my project settings (C/C++ Code Generation Runtime Library) to /MTd. Also I compiled Qt again, this time using following commands for a static building; originally found on this blog Static Qt with static CRT (VS 2008) 1- replaced -MD with -MT in lines QMAKE_CFLAGS_RELEASE and QMAKE_CFLAGS_DEBUG in %QDIR%\mkspecs\win32-msvc2008\qmake.conf 2- nmake confclean 3- configure -static -platform win32-msvc2008 -no-webkit 4- nmake sub-src I compiled Qt successfully. But when I tried again to compile my application, it gave me some strange errors. 1>Linking... 1>qtmaind.lib(qtmain_win.obj) : error LNK2005: "public: bool __thiscall QBasicAtomicInt::deref(void)" (?deref@QBasicAtomicInt@@QAE_NXZ) already defined in QtCored4.lib(QtCored4.dll) 1>qtmaind.lib(qtmain_win.obj) : error LNK2005: "public: bool __thiscall QBasicAtomicInt::operator!=(int)const " (??9QBasicAtomicInt@@QBE_NH@Z) already defined in QtCored4.lib(QtCored4.dll) 1>qtmaind.lib(qtmain_win.obj) : error LNK2005: "public: __thiscall QString::~QString(void)" (??1QString@@QAE@XZ) already defined in QtCored4.lib(QtCored4.dll) I changed some lib files but with each change, situation got worse; for example I tried to use QtCored.lib instead of QtCored4.lib because it is newly created after compilation. I think I've missed something in building static Qt libs. Thanks.

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  • Objective-C autorelease pool not releasing object

    - by Chris
    Hi I am very new to Objective-C and was reading through memory management. I was trying to play around a bit with the NSAutoreleasePool but somehow it wont release my object. I have a class with a setter and getter which basically sets a NSString *name. After releasing the pool I tried to NSLog the object and it still works but I guess it should not? @interface TestClass : NSObject { NSString *name; } - (void) setName: (NSString *) string; - (NSString *) name; @end @implementation TestClass - (void) setName: (NSString *) string { name = string; } - (NSString *) name { return name; } @end int main (int argc, const char * argv[]) { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; TestClass *var = [[TestClass alloc] init]; [var setName:@"Chris"]; [var autorelease]; [pool release]; // This should not be possible? NSLog(@"%@",[var name]); return 0; }

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  • Run AppleScript with Elevated Privileges from Objective C

    - by cygnl7
    I'm attempting to execute an uninstaller (written in AppleScript) through AuthorizationExecuteWithPrivileges. I'm setting up my rights after creating an empty auth ref like so: char *tool = "/usr/bin/osascript"; AuthorizationItem items = {kAuthorizationRightExecute, strlen(tool), tool, 0}; AuthorizationRights rights = {sizeof(items)/sizeof(AuthorizationItem), &items}; AuthorizationFlags flags = kAuthorizationFlagDefaults | kAuthorizationFlagExtendRights | kAuthorizationFlagPreAuthorize | kAuthorizationFlagInteractionAllowed; status = AuthorizationCopyRights(authorizationRef, &rights, NULL, flags, NULL); Later I call: status = AuthorizationExecuteWithPrivileges(authorizationRef, tool, kAuthorizationFlagDefaults, (char *const *)args, NULL); On Snow Leopard this works fine, but on Leopard I get the following in syslog.log: Apr 19 15:30:09 hostname /usr/bin/osascript[39226]: OpenScripting.framework - 'gdut' event blocked in process with mixed credentials (issetugid=0 uid=501 euid=0 gid=20 egid=20) Apr 19 15:30:12: --- last message repeated 1 time --- ... Apr 19 15:30:12 hostname [0x0-0x2e92e9].com.example.uninstaller[39219]: /var/folders/vm/vmkIi0nYG8mHMrllaXaTgk+++TI/-Tmp-/TestApp_tmpfiles/Uninstall.scpt: Apr 19 15:30:12 hostname [0x0-0x2e92e9].com.example.uninstaller[39219]: execution error: «constant afdmasup» doesn’t understand the «event earsffdr» message. (-1708) After researching this for a few hours my first guess is that Leopard somehow doesn't want to do what I'm doing because it knows it's in a setuid situation and blocks calls that ask about user-specific things in the applescript. Am I going about this all wrong? I just want to run the equivalent of "sudo /usr/bin/osascript ..." Edit: FWIW, the first line that causes the "execution error" is: set userAppSupportPath to (POSIX path of (path to application support folder from user domain)) However, even with an empty script (on run argv, end run and that's it) I still get the 'gdut' message.

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  • How can I work around the fact that in C++, sin(M_PI) is not 0?

    - by Adam Doyle
    In C++, const double Pi = 3.14159265; cout << sin(Pi); // displays: 3.58979e-009 it SHOULD display the number zero I understand this is because Pi is being approximated, but is there any way I can have a value of Pi hardcoded into my program that will return 0 for sin(Pi)? (a different constant maybe?) In case you're wondering what I'm trying to do: I'm converting polar to rectangular, and while there are some printf() tricks I can do to print it as "0.00", it still doesn't consistently return decent values (in some cases I get "-0.00") The lines that require sin and cosine are: x = r*sin(theta); y = r*cos(theta); BTW: My Rectangular - Polar is working fine... it's just the Polar - Rectangular Thanks! edit: I'm looking for a workaround so that I can print sin(some multiple of Pi) as a nice round number to the console (ideally without a thousand if-statements) edit: In case anyone's curious, this was what I landed on: double sin2(double theta) // in degrees { double s = sin(toRadians(theta)); if (fabs(s - (int)s) < 0.000001) { return floor(s + 0.5); } return s; } where toRadians() is a macro that converts to radians

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  • Applying policy based design question

    - by Arthur
    I've not read the Modern C++ Design book but have found the idea of behavior injection through templates interesting. I am now trying to apply it myself. I have a class that has a logger that I thought could be injected as a policy. The logger has a log() method which takes an std::string or std::wstring depending on its policy: // basic_logger.hpp template<class String> class basic_logger { public: typedef String string_type; void log(const string_type & s) { ... } }; typedef basic_logger<std::string> logger; typedef basic_logger<std::wstring> wlogger; // reader.hpp template<class Logger = logger> class reader { public: typedef Logger logger_type; void read() { _logger.log("Reading..."); } private: logger_type _logger; }; Now the questing is, should the reader take a Logger as an argument, like above, or should it take a String and then instantiate a basic_logger as an instance variable? Like so: template<class String> class reader { public: typedef String string_type; typedef basic_logger<string_type> logger_type; // ... private: logger_type _logger; }; What is the right way to go?

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  • How to pass parameters to manage_shared_memory.construct() in Boost.Interprocess

    - by recipriversexclusion
    I've stared at the Boost.Interprocess documentation for hours but still haven't been able to figure this out. In the doc, they have an example of creating a vector in shared memory like so: //Define an STL compatible allocator of ints that allocates from the managed_shared_memory. //This allocator will allow placing containers in the segment typedef allocator<int, managed_shared_memory::segment_manager> ShmemAllocator; //Alias a vector that uses the previous STL-like allocator so that allocates //its values from the segment typedef vector<int, ShmemAllocator> MyVector; int main(int argc, char *argv[]) { //Create a new segment with given name and size managed_shared_memory segment(create_only, "MySharedMemory", 65536); //Initialize shared memory STL-compatible allocator const ShmemAllocator alloc_inst (segment.get_segment_manager()); //Construct a vector named "MyVector" in shared memory with argument alloc_inst MyVector *myvector = segment.construct<MyVector>("MyVector")(alloc_inst); Now, I understand this. What I'm stuck is how to pass a second parameter to segment.construct() to specify the number of elements. The interprocess document gives the prototype for construct() as MyType *ptr = managed_memory_segment.construct<MyType>("Name") (par1, par2...); but when I try MyVector *myvector = segment.construct<MyVector>("MyVector")(100, alloc_inst); I get compilation errors. My questions are: Who actually gets passed the parameters par1, par2 from segment.construct, the constructor of the object, e.g. vector? My understanding is that the template allocator parameter is being passed. Is that correct? How can I add another parameter, in addition to alloc_inst that is required by the constructor of the object being created in shared memory? There's very little information other than the terse Boost docs on this.

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  • Strange problem with vectors.

    - by Catalin Dumitru
    I have a really strange problem with stl vectors in which the wrong destructor is called for the right object when I call the erase method if that makes any sense. My code looks something like this: for(vector<Category>::iterator iter = this->children.begin(); iter != this->children.end(); iter++) { if((*iter).item == item) { this->children.erase(iter); return; } ------------------------- } It's just a simple function that finds the element in the vector which has some item to be searched, and removes said element from the vector. My problem is than when the erase function is called, and thus the object which the iterator is pointing at is being destroyed, the wrong destructor is being called. More specific the destructor of the last element in the vector is being called, and not of the actual object being removed. Thus the memory is being removed from the wrong object, which will still be an element in the vector, and the actual object which is removed from the vector, still has all of it's memory intact. The costructor of the object looks like this: Category::Category(const Category &from) { this->name = from.name; for(vector<Category>::const_iterator iter = from.children.begin(); iter != from.children.end(); iter++) this->children.push_back((*iter)); this->item = new QTreeWidgetItem; } And the destructor Category::~Category() { this->children.clear(); if(this->item != NULL) { QTreeWidgetItem* parent = this->item->parent(); if(parent != NULL) parent->removeChild(this->item); delete this->item; } }

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  • How to deserialize an element as an XmlNode?

    - by mackenir
    When using Xml serialization in C#, I want to deserialize a part of my input XML to an XmlNode. So, given this XML: <Thing Name="George"> <Document> <subnode1/> <subnode2/> </Document> </Thing> I want to deserialize the Document element to an XmlNode. Below is my attempt which given the XML above, sets Document to the 'subnode1' element rather than the 'Document' element. How would I get the code to set the Document property to the Document element? using System; using System.IO; using System.Xml; using System.Xml.Serialization; [Serializable] public class Thing { [XmlAttribute] public string Name {get;set;} public XmlNode Document { get; set; } } class Program { static void Main() { const string xml = @" <Thing Name=""George""> <Document> <subnode1/> <subnode2/> </Document> </Thing>"; var s = new XmlSerializer(typeof(Thing)); var thing = s.Deserialize(new StringReader(xml)) as Thing; } } However, when I use an XmlSerializer to deserialize the XML above to an instance of Thing, the Document property contains the child element 'subnode1', rather than the 'doc' element. How can I get the XmlSerializer to set Document to an XmlNode containing the 'doc' element.

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  • Problem in encoding and decoding the string in Iphone sdk

    - by monish
    HI Guys, Here I am having a problem In encoding/decoding the strings. Actually I had a string which I am encoding it using the base64.which was working fine. And now I need to decode the string that was encoded before and want to print it. I code I written as: I imported the base64.h and base64.m files into my application which contains the methods as: + (NSData *) dataWithBase64EncodedString:(NSString *) string; - (id) initWithBase64EncodedString:(NSString *) string; - (NSString *) base64EncodingWithLineLength:(unsigned int) lineLength; And the code in my view controller where I encode the String is: - (id)init { if (self = [super init]) { // Custom initialization userName = @"Sekhar"; password = @"Bethalam"; } return self; } -(void)reloadView { NSString *authStr = [NSString stringWithFormat:@"%@:%@",userName,password]; NSData *authData = [authStr dataUsingEncoding:NSASCIIStringEncoding]; NSString *authValue = [NSString stringWithFormat:@"%@", [authData base64EncodingWithLineLength:30]]; NSLog(authValue); //const char *str = authValue; //NSString *decStr = [StringEncryption DecryptString:authValue]; //NSLog(decStr); //NSData *decodeData = [NSData decode:authValue]; //NSString *decStr = [NSString stringWithFormat:@"%@",decodeData]; //NSStr //NSLog(decStr); } -(void)viewWillAppear:(BOOL)animated { [self reloadView]; } and now I want to decode the String that I encoded. But I dont know How to do that.can anyone suggest me with code how to get it. Anyone's help will be much appreciated. Thank you, Monish.

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  • Delphi access violation assigning local variable

    - by Justin
    This seems like the simplest thing in the world and I'm ready to pull my hair out over it. I have a unit that looks like this ; Unit myUnit; // ... //normal declarations //... Public //bunch of procedures including Procedure myProcedure; const //bunch of constants var //bunch of vars including myCounter:integer; Implementation Uses //(all my uses) // All of my procedures including Procedure myProcedure; try // load items from file to TListBox - this all works except on EReadError do begin // handle exception end; end; //try myCounter:=0; // <-- ACCESS VIOLATION HERE while myCounter //...etc It's a simple assignment of a variable and I have no idea why it is doing this. I've tried declaring the variable local to the unit, to the procedure, globally - no matter where I try to do it I can't assign a value of zero to an integer, declared anywhere, within this procedure without it throwing an access violation. I'm totally stumped. I'm calling the procedure from inside a button OnClick handler from within the same unit, but no matter where I call it from it throws the exception. The crazy thing is that I do the exact same thing in a dozen other places in units all over the program without problems. Why here? I'm at a total loss.

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