program output problem

[Gary Wessle]

Hi

the following code puts out
****************************************************************
~/myProg/epoch2string $ ./proj
Type 1 for epoch-to-text or 2 for text-to-epoch.
2
2007-2-28 10:50:00
1172581200
~/myProg/epoch2string $ ./proj
Type 1 for epoch-to-text or 2 for text-to-epoch.
2
2007-2-28 21:00:00
1172581200
****************************************************************

the same epoch for 2 different time_points, i.e
2007-2-28 21:00:00
2007-2-28 10:50:00
bot giving out
1172581200

here is the code, could some one please take a look and tell me whats
gone wrong.

thank you

****************************************************************
#include <iostream>
#include <string>
#include <ctime>


/* Returns local time epoch from a given time format
"2007-01-28 21:15:00" */
time_t asci2epoch(std::string s)
{
struct tm t_tm = { 0 };
// the time string
const char *t_str = s.c_str();
// get the values from the time string
sscanf(t_str, "%d-%d-%d %d:%d:%d", &(t_tm.tm_year), &(t_tm.tm_mon), &(t_tm.tm_mday), &(t_tm.tm_hour), &(t_tm.tm_min), &(t_tm.tm_sec));
// normalize ...
t_tm.tm_year -= 1900;
t_tm.tm_mon -= 1;
// the result :
time_t t = mktime(&t_tm);
t -= (1*60*60); // DST
return t;
}

int main()
{

std::cout << "Type 1 for epoch-to-text or 2 for text-to-epoch." << std::endl;
short opt;
std::cin >> opt;
if( opt == 1 )
{
time_t x;
std::cin >> x;
tm* p_tick = localtime( &x );
std::cout << "tick: " << asctime( p_tick ) << std::endl;
}
else if( opt == 2 )
{
std::string a;
std::cin >> a; // std::string a = "2007-2-5 8:45:00";
std::cout << asci2epoch(a) << std::endl;
}
else
std::cout << "wrong option." << std::endl;
}

 

[Victor Bazarov]

Hi

the following code puts out
****************************************************************
~/myProg/epoch2string $ ./proj
Type 1 for epoch-to-text or 2 for text-to-epoch.
2
2007-2-28 10:50:00
1172581200
~/myProg/epoch2string $ ./proj
Type 1 for epoch-to-text or 2 for text-to-epoch.
2
2007-2-28 21:00:00
1172581200
****************************************************************

the same epoch for 2 different time_points, i.e
2007-2-28 21:00:00
2007-2-28 10:50:00
bot giving out
1172581200

here is the code, could some one please take a look and tell me whats
gone wrong.

Inputting a string is wrong.

thank you

****************************************************************
#include <iostream>
#include <string>
#include <ctime>


/* Returns local time epoch from a given time format
"2007-01-28 21:15:00" */
time_t asci2epoch(std::string s)
{
struct tm t_tm = { 0 };
// the time string
const char *t_str = s.c_str();
// get the values from the time string
sscanf(t_str, "%d-%d-%d %d:%d:%d", &(t_tm.tm_year), &(t_tm.tm_mon),
&(t_tm.tm_mday), &(t_tm.tm_hour), &(t_tm.tm_min), &(t_tm.tm_sec));
// normalize ... t_tm.tm_year -= 1900;
t_tm.tm_mon -= 1;
// the result :
time_t t = mktime(&t_tm);
t -= (1*60*60); // DST
return t;
}

int main()
{

std::cout << "Type 1 for epoch-to-text or 2 for text-to-epoch." <<
std::endl; short opt;
std::cin >> opt;
if( opt == 1 )
{
time_t x;
std::cin >> x;
tm* p_tick = localtime( &x );
std::cout << "tick: " << asctime( p_tick ) << std::endl;
}
else if( opt == 2 )
{
std::string a;
std::cin >> a; // std::string a = "2007-2-5 8:45:00";

Check what you get in your string when you input it. Then read
about 'getline'.

std::cout << asci2epoch(a) << std::endl;
}
else
std::cout << "wrong option." << std::endl;
}

V

 

[Gary Wessle]

Inputting a string is wrong.


Check what you get in your string when you input it. Then read
about 'getline'.

I tried
getline( std::cin, a );
instead of
std::cin >> a;

but I am doing something wrong.
isn't
template<class Ch, class Tr, class A>
basic_istream<Ch, Tr>& getline(basic_istream<Ch, Tr>&,
basic_string<Ch, Tr, A>&);

 

[Thomas Tutone]

I tried
getline( std::cin, a );
instead of
std::cin >> a;

but I am doing something wrong.

std::getline(std::cin, a);

Best regards,

Tom

 

[Gary Wessle]

std::getline(std::cin, a);

the code does not wait for entry and it ends prematurely when
selecting the "2" option.

#include <iostream>
#include <string>
#include <ctime>


/* Returns local time epoch from a given time format
"2007-01-28 21:15:00" */
time_t asci2epoch(std::string s)
{
struct tm t_tm = { 0 };
// the time string
const char *t_str = s.c_str();
// get the values from the time string
sscanf(t_str, "%d-%d-%d %d:%d:%d", &(t_tm.tm_year), &(t_tm.tm_mon), &(t_tm.tm_mday), &(t_tm.tm_hour), &(t_tm.tm_min), &(t_tm.tm_sec));
// normalize ...
t_tm.tm_year -= 1900;
t_tm.tm_mon -= 1;
// the result :
time_t t = mktime(&t_tm);
t -= (1*60*60); // DST
return t;
}

int main()
{

std::cout << "Type 1 for epoch-to-text or 2 for text-to-epoch." << std::endl;
short opt;
std::cin >> opt;
if( opt == 1 )
{
time_t x;
std::cin >> x;
tm* p_tick = localtime( &x );
std::cout << "tick: " << asctime( p_tick ) << std::endl;
}
else if( opt == 2 )
{
std::string a;
std::getline( std::cin, a); // std::string a = "2007-2-5 8:45:00";
std::cout << asci2epoch(a) << std::endl;
}
else
std::cout << "wrong option." << std::endl;
}

 

[Ian Collins]

the code does not wait for entry and it ends prematurely when
selecting the "2" option.

It's picking up the newline character that wasn't read from cin when the
option is input.

 

[Victor Bazarov]

It's picking up the newline character that wasn't read from cin when
the option is input.

In order to overcome this, the 'getline' should be preceded by
'cin.ignore', probably. Or just read out a single character...

V