Undefined reference to 'getpass' in c - c

#include <stdio.h>
#include <unistd.h>
int main()
{
char *itm;
char *qnt;
qnt,itm = getpass("");
printf("%s %s ",qnt,itm);
return 0;
}
So if i run this code in online compiler like replit , it runs without error . But when i run it in codeblock , it throws an error stating undefined reference to 'getpass' . how to fix this ?

Related

XCode EXC_BAD_ACCESS by Changing Variable Name

Take this simple program and run it in Xcode:
#include <stdio.h>
#include "inttypes.h"
struct {
int32_t nwgts;
;
} clbint_;
#define clbint_1 clbint_
int main()
{
printf("clbint_1.nwgts: %d\n",clbint_1.nwgts);
clbint_1.nwgts=1; //Crash here
printf("clbint_1.nwgts: %d\n",clbint_1.nwgts);
return 0;
}
And when you run it you will get a crash on the line indicated that just says Thread 1: EXC_BAD_ACCESS (code=2, address=0x10078e18c). But if you change clbint_ to clbinta_ like this:
#include <stdio.h>
#include "inttypes.h"
struct {
int32_t nwgts;
;
} clbinta_;
#define clbint_1 clbinta_
int main()
{
printf("clbint_1.nwgts: %d\n",clbint_1.nwgts);
clbint_1.nwgts=1;
printf("clbint_1.nwgts: %d\n",clbint_1.nwgts);
return 0;
}
The results print exactly as I expect:
clbint_1.nwgts: 0
clbint_1.nwgts: 1
I am trying to understand why this is happening, clearly it has something to do with the variable name clbint_ but why does this behavior occur?

#include errors detected in vs code for c lang

I don't know what to do
please can any one help me
I'm trying to use c in vs code for the first time
#include <stdio.h>
int main (void)
{
printf("Hello, World!");
}
The problem

Why am I getting an error for my symbolic link program?

So I'm trying to compile this code [symbolic_link.c] that will let me create a symbolic link for a protected file.
#include <stdio.h>
#include <unistd.h>
#include <string.h>
int symlink(const char *, const char *);
int main(int argc, char * argv[]) {
unlink(argv[1]);
symlink("./passwd",argv[1]);
}
When I compile, the error I get is:
symbolic_link.c:(.text+0x32): undefined reference to `symlink'
collect2.exe: error: ld returned 1 exit status
The code compiles properly on Linux but not on Windows 10 minGW.
How can I fix this?

moved from cygwin to VisualStudio2013, error LNK2019, snprintf(), c

I'm trying to run a unix compiler-project written in c with MS Visual-Studio 2013 and I can't get rid of the following error:
error LNK2019: unresolved external symbol "_snprintf" referenced in
function "PUBLIC void SyntaxError( int Expected, TOKEN CurrentToken )"
If I get it right it is a problem where VisualStudio can't find the body/declaration from the snprintf() function, which should be defined in stdio.h.
The project works fine with cygwin. I had to add _CRT_SECURE_NO_WARNINGS to preprocessor settings to get this far, but i don't think that has a influence.
Here is the named function:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include "line.h"
#include "strtab.h"
#include "scanner.h"
[..code..]
PUBLIC void SyntaxError( int Expected, TOKEN CurrentToken )
{
char s[M_LINE_WIDTH+2];
snprintf( s, sizeof(s), "Syntax: Expected %s, got %s\n", Tokens[Expected], Tokens[CurrentToken.code] );
Error( s, CurrentToken.pos );
}
If you can help me or there is anything else you need to know please tell me. It's my 3rd day now and I am running out of ideas ;).
So far... Tobias
The name of this function with the MSVC compiler is _snprintf() with an underscore.

segmentation fault (core dumped) error when using time function

Hello i am new to Linux and c programming so this might be stupid question but i couldn't find an answer.
I am writing a home work and they want me to print the execution time at the end of program using time() function, so when i used the function in my program i got the message segmentation fault (core dumped) and when i remove it the program works agine.
Then i created a test file in the code below :
#include <stdio.h>
int main()
{
time();
return 0;
}
And i got the same error message.
Also tried :
#include <stdio.h>
int main()
{
time(NULL);
return 0;
}
And
#include <stdio.h>
#include <time.h>
int main()
{
time_t t;
time(&t);
return 0;
}
And got the same error.
so what i am doing wrong ?
Thanks
In your first two examples, you forget to include time.h. That is the cause of the segmentation fault in those examples. If you're using gcc, try compiling with -Wall (which turns on all warnings). You should get a warning indicating an implicit declaration of function "time" - in other words, that you've forgotten to include time.h.
Your final example, however, works fine for me. If you keep getting a segmentation fault, however, try debugging with gdb.
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main(void)
{
time_t now;
time(&now);
printf("%s", ctime(&now));
return EXIT_SUCCESS;
}

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