getwc(3C) getwc(3C)
NAME
getwc(), getwchar(), fgetwc() - get a wide character from a stream file
SYNOPSIS
Obsolescent Interfaces
Remarks
These functions are compliant with the XPG4 Worldwide Portability Interface wide-character I/O functions. They parallel the 8-bit charac-
ter I/O functions defined in getc(3S).
DESCRIPTION
Returns the next character from the named input
stream, converts that to the corresponding wide character and moves the file pointer ahead one character in stream. is
defined as and are defined both as macros and as functions.
Behaves like but is a function rather than a macro.
Definitions for these functions, the types and the value are provided in header file
Obsolescent Interfaces
get a wide character from a stream file.
APPLICATION USAGE
After or is applied to a stream, the stream becomes wide-oriented (see orientation(5)).
RETURN VALUE
Upon successful completion, and return the next wide-character read from stream for converted to a type If the stream is at end-of-file,
the end-of-file indicator for the stream is set and is returned.
When the file corresponding to an open stream gets extended after the end-of-file is reached, any subsequent calls to these functions will
succeed and the end-of-file indicator will remain set. However, in the UNIX2003 standards environment (see standards(5)), these functions
will return and the end-of-file indicator will still remain set.
If a read error occurs, the error indicator for the stream is set, is set to indicate the error, and is returned.
and can be used to distinguish between an error condition and an end-of-file condition.
ERRORS
and fail if data needs to be read into the stream's buffer, and:
The flag is set for the file descriptor underlying stream and the process would be delayed in the read operation.
The file descriptor underlying
stream is not a valid file descriptor open for reading.
The read operation was terminated due to the receipt of a signal,
and either no data was transferred or the implementation does not report partial transfer for this file.
A physical I/O error has occurred, or the process is a
member of a background process and is attempting to read from its controlling terminal, and either the process is ignoring
or blocking the signal or the process group of the process is orphaned.
The data obtained from the input stream
does not form a valid wide character.
Additional values may be set by the underlying function (see read(2)).
EXTERNAL INFLUENCES
Environment Variables
category determines how wide-character conversions are done.
International Code Set Support
Single- and multibyte character code sets are supported.
WARNINGS
If the value returned by or is stored into a type variable then compared against the constant the comparison may never succeed because
extension of a to a is machine-dependent.
and are obsolescent interfaces supported only for compatibility with existing DCE applications. New multithreaded applications should use
and
AUTHOR
was developed by OSF and HP.
SEE ALSO
fclose(3S), ferror(3S), flockfile(3S), fopen(3S), fread(3S), fgetws(3C), orientation(5), putwc(3C), read(2), scanf(3S), orientation(5),
standards(5), thread_safety(5).
STANDARDS CONFORMANCE
getwc(3C)