fputc(3p) — Linux manual page
FPUTC(3P) POSIX Programmer's Manual FPUTC(3P)
PROLOG
This manual page is part of the POSIX Programmer's Manual. The
Linux implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
NAME
fputc — put a byte on a stream
SYNOPSIS
#include <stdio.h>
int fputc(int c, FILE *stream);
DESCRIPTION
The functionality described on this reference page is aligned
with the ISO C standard. Any conflict between the requirements
described here and the ISO C standard is unintentional. This
volume of POSIX.1‐2017 defers to the ISO C standard.
The fputc() function shall write the byte specified by c
(converted to an unsigned char) to the output stream pointed to
by stream, at the position indicated by the associated file-
position indicator for the stream (if defined), and shall advance
the indicator appropriately. If the file cannot support
positioning requests, or if the stream was opened with append
mode, the byte shall be appended to the output stream.
The last data modification and last file status change timestamps
of the file shall be marked for update between the successful
execution of fputc() and the next successful completion of a call
to fflush() or fclose() on the same stream or a call to exit() or
abort().
RETURN VALUE
Upon successful completion, fputc() shall return the value it has
written. Otherwise, it shall return EOF, the error indicator for
the stream shall be set, and errno shall be set to indicate the
error.
ERRORS
The fputc() function shall fail if either the stream is
unbuffered or the stream's buffer needs to be flushed, and:
EAGAIN The O_NONBLOCK flag is set for the file descriptor
underlying stream and the thread would be delayed in the
write operation.
EBADF The file descriptor underlying stream is not a valid file
descriptor open for writing.
EFBIG An attempt was made to write to a file that exceeds the
maximum file size.
EFBIG An attempt was made to write to a file that exceeds the
file size limit of the process.
EFBIG The file is a regular file and an attempt was made to
write at or beyond the offset maximum.
EINTR The write operation was terminated due to the receipt of a
signal, and no data was transferred.
EIO A physical I/O error has occurred, or the process is a
member of a background process group attempting to write
to its controlling terminal, TOSTOP is set, the calling
thread is not blocking SIGTTOU, the process is not
ignoring SIGTTOU, and the process group of the process is
orphaned. This error may also be returned under
implementation-defined conditions.
ENOSPC There was no free space remaining on the device containing
the file.
EPIPE An attempt is made to write to a pipe or FIFO that is not
open for reading by any process. A SIGPIPE signal shall
also be sent to the thread.
The fputc() function may fail if:
ENOMEM Insufficient storage space is available.
ENXIO A request was made of a nonexistent device, or the request
was outside the capabilities of the device.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
Section 2.5, Standard I/O Streams, ferror(3p), fopen(3p),
getrlimit(3p), putc(3p), puts(3p), setbuf(3p), ulimit(3p)
The Base Definitions volume of POSIX.1‐2017, stdio.h(0p)
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic
form from IEEE Std 1003.1-2017, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The
Open Group Base Specifications Issue 7, 2018 Edition, Copyright
(C) 2018 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any
discrepancy between this version and the original IEEE and The
Open Group Standard, the original IEEE and The Open Group
Standard is the referee document. The original Standard can be
obtained online at http://www.opengroup.org/unix/online.html .
Any typographical or formatting errors that appear in this page
are most likely to have been introduced during the conversion of
the source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2017 FPUTC(3P)
Pages that refer to this page: stdio.h(0p), fprintf(3p), fputs(3p), fwrite(3p), perror(3p), psiginfo(3p), putc(3p), putchar(3p), puts(3p)