NAME

std::basic_istream::getline - std::basic_istream::getline

Synopsis

basic_istream& getline( char_type* s, std::streamsize count ); (1)
basic_istream& getline( char_type* s, std::streamsize count, char_type delim ); (2)

Extracts characters from stream until end of line or the specified delimiter delim.

The first overload is equivalent to getline(s, count, widen('\n')).

Behaves as UnformattedInputFunction. After constructing and checking the sentry
object, extracts characters from *this and stores them in successive locations of
the array whose first element is pointed to by s, until any of the following occurs
(tested in the order shown):

1. end of file condition occurs in the input sequence (in which case
setstate(eofbit) is executed)
2. the next available character c is the delimiter, as determined by Traits::eq(c,
delim). The delimiter is extracted (unlike basic_istream::get()) and counted
towards gcount(), but is not stored.
3. count-1 characters have been extracted (in which case setstate(failbit) is
executed).

If the function extracts no characters (e.g. if count < 1), setstate(failbit) is
executed.

In any case, if count > 0, it then stores a null character CharT() into the next
successive location of the array and updates gcount().

Notes

Because condition #2 is tested before condition #3, the input line that exactly fits
the buffer does not trigger failbit.

Because the terminating character is counted as an extracted character, an empty
input line does not trigger failbit.

Parameters

s - pointer to the character string to store the characters to
count - size of character string pointed to by s
delim - delimiting character to stop the extraction at. It is extracted but not
stored.

Return value

*this

Exceptions

failure if an error occurred (the error state flag is not goodbit) and exceptions()
is set to throw for that state.

If an internal operation throws an exception, it is caught and badbit is set. If
exceptions() is set for badbit, the exception is rethrown.

Example

// Run this code

#include <iostream>
#include <sstream>
#include <vector>
#include <array>

int main()
{
std::istringstream input("abc|def|gh");
std::vector<std::array<char, 4>> v;

// note: the following loop terminates when std::ios_base::operator bool()
// on the stream returned from getline() returns false
for (std::array<char, 4> a; input.getline(&a[0], 4, '|'); ) {
v.push_back(a);
}

for (auto& a : v) {
std::cout << &a[0] << '\n';
}
}

Output:

abc
def
gh