| CARVIEW |
Select Language
HTTP/1.1 301 Moved Permanently
Server: nginx
Date: Sat, 26 Jul 2025 08:55:29 GMT
Content-Type: text/html; charset=UTF-8
Transfer-Encoding: chunked
Connection: keep-alive
Location: /reference/fstream/basic_filebuf/uflow/
HTTP/1.1 200 OK
Server: nginx
Date: Sat, 26 Jul 2025 08:55:30 GMT
Content-Type: text/html; charset=utf-8
Transfer-Encoding: chunked
Connection: keep-alive
ETag: W/"789f-uperSgzvRIktvfBn4UhQgw2J6nA"
Content-Encoding: gzip
Returns the character at the current input position, and advances the input position pointer.
Before that, this function attempts to read characters from the associated file and -if the object keeps an intermediate buffer- makes them available by altering the internal input buffer pointers (gptr, egptr and eback) as needed.
If there are no more characters available and the function did not succeed in reading more characters from the associated file, it returns the end-of-file value (
This virtual member function overrides the inherited member basic_streambuf::uflow, called by members such as sbumpc to request a new character when there are no read positions available at the get pointer (gptr).
The behavior of this member function is similar to that of underflow, except that this function advances the input position.
If there are no more characters to read from the controlled input sequence, it returns the end-of-file value (
Member type int_type is an integral type able to represent any character value or the special end-of-file value.
Concurrent access to the same file stream buffer object may introduce data races.
Reference
C library:
- <cassert> (assert.h)
- <cctype> (ctype.h)
- <cerrno> (errno.h)
-
<cfenv> (fenv.h)C++11
- <cfloat> (float.h)
-
<cinttypes> (inttypes.h)C++11
- <ciso646> (iso646.h)
- <climits> (limits.h)
- <clocale> (locale.h)
- <cmath> (math.h)
- <csetjmp> (setjmp.h)
- <csignal> (signal.h)
- <cstdarg> (stdarg.h)
-
<cstdbool> (stdbool.h)C++11
- <cstddef> (stddef.h)
-
<cstdint> (stdint.h)C++11
- <cstdio> (stdio.h)
- <cstdlib> (stdlib.h)
- <cstring> (string.h)
-
<ctgmath> (tgmath.h)C++11
- <ctime> (time.h)
-
<cuchar> (uchar.h)C++11
- <cwchar> (wchar.h)
- <cwctype> (wctype.h)
Containers:
-
<array>C++11
- <deque>
-
<forward_list>C++11
- <list>
- <map>
- <queue>
- <set>
- <stack>
-
<unordered_map>C++11
-
<unordered_set>C++11
- <vector>
-
Input/Output:
Multi-threading:
-
<atomic>C++11
-
<condition_variable>C++11
-
<future>C++11
-
<mutex>C++11
-
<thread>C++11
-
Other:
- <algorithm>
- <bitset>
-
<chrono>C++11
-
<codecvt>C++11
- <complex>
- <exception>
- <functional>
-
<initializer_list>C++11
- <iterator>
- <limits>
- <locale>
- <memory>
- <new>
- <numeric>
-
<random>C++11
-
<ratio>C++11
-
<regex>C++11
- <stdexcept>
- <string>
-
<system_error>C++11
-
<tuple>C++11
-
<type_traits>C++11
-
<typeindex>C++11
- <typeinfo>
- <utility>
- <valarray>
<fstream>
class templates
classes
basic_filebuf
- basic_filebuf::~basic_filebuf
- basic_filebuf::basic_filebuf
public members
protected virtual members
non-member overloads
-
swap (basic_filebuf)C++11
-
- Reference
- <fstream>
- basic_filebuf
- uflow
protected virtual member function
<fstream>
std::basic_filebuf::uflow
int_type uflow();
Get character on overflow and advance position
Before that, this function attempts to read characters from the associated file and -if the object keeps an intermediate buffer- makes them available by altering the internal input buffer pointers (gptr, egptr and eback) as needed.
If there are no more characters available and the function did not succeed in reading more characters from the associated file, it returns the end-of-file value (
traits_type::eof()), indicating failure.This virtual member function overrides the inherited member basic_streambuf::uflow, called by members such as sbumpc to request a new character when there are no read positions available at the get pointer (gptr).
The behavior of this member function is similar to that of underflow, except that this function advances the input position.
Parameters
noneReturn Value
The character at the current position of the controlled input sequence, converted to a value of type int_type using member traits_type::to_int_type.If there are no more characters to read from the controlled input sequence, it returns the end-of-file value (
traits_type::eof()).Member type int_type is an integral type able to represent any character value or the special end-of-file value.
Data races
Modifies the basic_filebuf object.Concurrent access to the same file stream buffer object may introduce data races.
Exception safety
Basic guarantee: if an exception is thrown, the file stream buffer is in a valid state.See also
- basic_filebuf::underflow
- Get character on underflow (protected virtual member function)
- basic_streambuf::uflow
- Get character on underflow and advance position (protected virtual member function)
- basic_streambuf::sbumpc
- Get current character and advance to next position (public member function)
Home page | Privacy policy
© cplusplus.com, 2000-2025 - All rights reserved - v3.3.4s
Spotted an error? contact us
© cplusplus.com, 2000-2025 - All rights reserved - v3.3.4s
Spotted an error? contact us