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

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

       #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);

       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).

       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.

       For   an	  explanation	of   the  terms	 used  in  this	 section,  see

       |Interface		  | Attribute	  | Value   |
       |fgetc(), fgets(), getc(), | Thread safety | MT-Safe |
       |getchar(), ungetc()	  |		  |	    |

       POSIX.1-2001, POSIX.1-2008, C89, C99.

       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.

       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)

       This  page  is  part of release 4.10 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

GNU				  2015-08-08			      FGETC(3)