ungetc(3)



FGETC(3)                   Linux Programmer's Manual                  FGETC(3)

NAME
       fgetc, fgets, getc, getchar, ungetc - input of characters and strings

SYNOPSIS
       #include <stdio.h>

       int fgetc(FILE *stream);

       char *fgets(char *s, int size, FILE *stream);

       int getc(FILE *stream);

       int getchar(void);

       int ungetc(int c, FILE *stream);

DESCRIPTION
       fgetc()  reads  the  next  character  from  stream and returns it as an
       unsigned char cast to an int, or EOF on end of file or error.

       getc() is equivalent to fgetc() except that it may be implemented as  a
       macro which evaluates stream more than once.

       getchar() is equivalent to getc(stdin).

       fgets()  reads in at most one less than size characters from stream and
       stores them into the buffer pointed to by s.  Reading  stops  after  an
       EOF  or a newline.  If a newline is read, it is stored into the buffer.
       A terminating null byte ('\0') is stored after the  last  character  in
       the buffer.

       ungetc()  pushes  c  back to stream, cast to unsigned char, where it is
       available for subsequent read operations.  Pushed-back characters  will
       be returned in reverse order; only one pushback is guaranteed.

       Calls  to the functions described here can be mixed with each other and
       with calls to other input functions from the stdio library for the same
       input stream.

       For nonlocking counterparts, see unlocked_stdio(3).

RETURN VALUE
       fgetc(),  getc() and getchar() return the character read as an unsigned
       char cast to an int or EOF on end of file or error.

       fgets() returns s on success, and NULL on error or  when  end  of  file
       occurs while no characters have been read.

       ungetc() returns c on success, or EOF on error.

CONFORMING TO
       C89, C99, POSIX.1-2001.

       It  is  not  advisable  to  mix calls to input functions from the stdio
       library with low-level calls to read(2) for the file descriptor associ-
       ated  with  the  input  stream;  the results will be undefined and very
       probably not what you want.

SEE ALSO
       read(2), write(2), ferror(3), fgetwc(3), fgetws(3), fopen(3), fread(3),
       fseek(3),   getline(3),   gets(3),   getwchar(3),   puts(3),  scanf(3),
       ungetwc(3), unlocked_stdio(3), feature_test_macros(7)

COLOPHON
       This page is part of release 3.71 of the Linux  man-pages  project.   A
       description  of  the project, information about reporting bugs, and the
       latest    version    of    this    page,    can     be     found     at
       http://www.kernel.org/doc/man-pages/.

GNU                               2013-12-31                          FGETC(3)

Man(1) output converted with man2html
list of all man pages