Visit Our UNIX and Linux User Community

Linux and UNIX Man Pages

Test Your Knowledge in Computers #493
Difficulty: Medium
When a program executes, each command executes one after the other, top-to-bottom. This is known as inconsequential control flow.
True or False?
Linux & Unix Commands - Search Man Pages

clearerr(3s) [bsd man page]

FERROR(3S)																FERROR(3S)

ferror, feof, clearerr, fileno - stream status inquiries SYNOPSIS
#include <stdio.h> feof(stream) FILE *stream; ferror(stream) FILE *stream clearerr(stream) FILE *stream fileno(stream) FILE *stream; DESCRIPTION
Feof returns non-zero when end of file is read on the named input stream, otherwise zero. Unless cleared by clearerr, the end-of-file indication lasts until the stream is closed. Ferror returns non-zero when an error has occurred reading or writing the named stream, otherwise zero. Unless cleared by clearerr, the error indication lasts until the stream is closed. Clearerr resets the error and end-of-file indicators on the named stream. Fileno returns the integer file descriptor associated with the stream, see open(2). Currently all of these functions are implemented as macros; they cannot be redeclared. SEE ALSO
fopen(3S), open(2) 4th Berkeley Distribution May 14, 1986 FERROR(3S)

Check Out this Related Man Page

FERROR(3)						   BSD Library Functions Manual 						 FERROR(3)

clearerr, clearerr_unlocked, feof, feof_unlocked, ferror, ferror_unlocked, fileno, fileno_unlocked -- check and reset stream status LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <stdio.h> void clearerr(FILE *stream); void clearerr_unlocked(FILE *stream); int feof(FILE *stream); int feof_unlocked(FILE *stream); int ferror(FILE *stream); int ferror_unlocked(FILE *stream); int fileno(FILE *stream); int fileno_unlocked(FILE *stream); DESCRIPTION
The function clearerr() clears the end-of-file and error indicators for the stream pointed to by stream. The function feof() tests the end-of-file indicator for the stream pointed to by stream, returning non-zero if it is set. The end-of-file indicator can only be cleared by the function clearerr(). The function ferror() tests the error indicator for the stream pointed to by stream, returning non-zero if it is set. The error indicator can only be reset by the clearerr() function. The function fileno() examines the argument stream and returns its integer descriptor. The clearerr_unlocked(), feof_unlocked(), ferror_unlocked(), and fileno_unlocked() functions are equivalent to clearerr(), feof(), ferror(), and fileno() respectively, except that the caller is responsible for locking the stream with flockfile(3) before calling them. These func- tions may be used to avoid the overhead of locking the stream and to prevent races when multiple threads are operating on the same stream. ERRORS
These functions should not fail and do not set the external variable errno. SEE ALSO
open(2), fdopen(3), flockfile(3), stdio(3) STANDARDS
The functions clearerr(), feof(), and ferror() conform to ISO/IEC 9899:1990 (``ISO C90''). BSD
January 10, 2003 BSD

Featured Tech Videos