FGETC(2) FGETC(2)
NAME
fgetc, getc, getchar, fputc, putc, putchar, ungetc, fgets,
gets, fputs, puts, fread, fwrite - Stdio input and output
SYNOPSIS
#include <stdio.h>
int fgetc(FILE *f)
int getc(FILE *f)
int getchar(void)
int fputc(int c, FILE *f)
int putc(int c, FILE *f)
int putchar(int c)
int ungetc(int c, FILE *f)
char *fgets(char *s, int n, FILE *f)
char *gets(char *s)
int fputs(char *s, FILE *f)
int puts(char *s)
long fread(void *ptr, long itemsize, long nitems, FILE
*stream)
long fwrite(void *ptr, long itemsize, long nitems, FILE
*stream)
DESCRIPTION
The functions described here work on open Stdio streams (see
fopen).
Fgetc returns as an int the next unsigned char from input
stream f. If the stream is at end-of-file, the end-of-file
indicator for the stream is set and fgetc returns EOF. If a
read error occurs, the error indicator for the stream is set
and fgetc returns EOF. Getc is like fgetc except that it is
implemented as a macro. Getchar is like getc except that it
always reads from stdin.
Ungetc pushes character c back onto the input stream f. The
pushed-back character will be returned by subsequent reads
in the reverse order of their pushing. A successful
Page 1 Plan 9 (printed 11/18/24)
FGETC(2) FGETC(2)
intervening fseek, fsetpos, or rewind on f discards any
pushed-back characters for f. One character of push-back is
guaranteed. Ungetc returns the character pushed back (con-
verted to unsigned char), or EOF if the operation fails. A
successful call to ungetc clears the end-of-file indicator
for the stream. The file position indicator for the stream
after reading or discarding all pushed-back characters is
the same as it was before the characters were pushed back.
Fputc writes character c (converted to unsigned char) to
output stream f at the position indicated by the position
indicator for the stream and advances the indicator appro-
priately. If the file cannot support positioning requests,
or if the stream was opened with append mode, the character
is appended to the output stream. Fputc returns the charac-
ter written or EOF if there was a write error. Putc is like
fputc but is implemented as a macro. Putchar is like putc
except that it always writes to stdout.
All other input takes place as if characters were read by
successive calls to fgetc and all other output takes place
as if characters were written by successive calls to fputc.
Fgets reads up to and including the next newline, but not
past end-of-file or more than n-1 characters, from stream f
into array s. A null character is written immediately after
the last character read into the array (if any characters
are read at all). Fgets returns s if successful, otherwise
a null pointer. Gets is similar to fgets except that it
always reads from stdin and it discards the terminating new-
line, if any. Gets does not check for overflow of the
receiving array, so its use is deprecated.
Fputs writes the string s to stream f, returning EOF if a
write error occurred, otherwise a nonnegative value. The
terminating null character is not written. Puts is the
same, writing to stdout.
Fread reads from the named input stream at most nitems of
data of size itemsize and the type of *ptr into a block
beginning at ptr. It returns the number of items actually
read.
Fwrite appends to the named output stream at most nitems of
data of size itemsize and the type of *ptr from a block
beginning at ptr. It returns the number of items actually
written.
SOURCE
/sys/src/libstdio
SEE ALSO
Page 2 Plan 9 (printed 11/18/24)
FGETC(2) FGETC(2)
read(2), fopen(2), bio(2)
BUGS
Stdio does not handle UTF or runes; use Bio instead.
Page 3 Plan 9 (printed 11/18/24)