Man Pages

gets(3) - phpMan gets(3) - phpMan

Command: man perldoc info search(apropos)  


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



NAME
       fgetc, fgets, getc, getchar, gets, 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);

       char *gets(char *s);

       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).

       gets() reads a line from stdin into the buffer pointed to by s until either a terminating newline or EOF, which
       it replaces with '\0'.  No check for buffer overrun is performed (see BUGS below).

       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 '\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 non-locking 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.

       gets()  and  fgets() return 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.  LSB deprecates gets().  POSIX.1-2008 removes the specification of gets().

BUGS
       Never use gets().  Because it is impossible to tell without knowing the data in  advance  how  many  characters
       gets()  will  read,  and  because  gets()  will  continue to store characters past the end of the buffer, it is
       extremely dangerous to use.  It has been used to break computer security.  Use fgets() instead.

       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 associated 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),  getwchar(3),
       puts(3), scanf(3), ungetwc(3), unlocked_stdio(3)

COLOPHON
       This  page  is part of release 3.22 of the Linux man-pages project.  A description of the project, and informa-
       tion about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



GNU                               2008-08-06                           GETS(3)