Manual section 3S

clearerr - status inquiries
ctermid - generate file name for terminal
cuserid - get character login name of the user
fclose - close a stream
fclose, fflush - close or flush a stream
fdopen - associate a stream with a file descriptor
feof - stream status inquiries
ferror, feof, clearerr, fileno - stream status inquiries
fflush - flush a stream
fgetc - get next character (byte) from a stream
fgets - get a line of, at most, n characters from a stream
fgetwc - get next wide character from a named stream
fileno - stream status inquiries
flock: flockfile, ftrylockfile, funlockfile - standard I/O synchronization functions
flockfile - grant thread ownership of a file
fopen - open a stream
fopen, fopen64, freopen, freopen64, fdopen - open a stream
fopen64 - open a stream (supports large files)
fprintf, printf, snprintf, sprintf, fsprintf, vfprintf, vprintf, vsnprinf, vsprintf, vfsprintf - place print output on stream
fputc - put a character on a stream
fputs - put a string on a named stream
fputwc - put wide character on a stream
fread - binary input to an array
fread, fwrite - binary input/output
freopen - open a named file in place of the open stream
freopen64 - open a named file in place of the open stream (supports large files)
fscanf - convert formatted input read from a named stream
fscanf, scanf, sscanf, vfscanf, vscanf, vsscanf - convert formatted input
fseek - reposition a file pointer in a stream
fseek, rewind, ftell - reposition a file pointer in a stream
fseeko - reposition a file pointer in a stream
fseeko, fseeko64, ftello, ftello64 - reposition a file pointer in a stream
fseeko64 - reposition a file pointer in a stream (supports large files)
fsprintf - place print output up to n chars in character array, reusing buffer
ftell - return offset of current byte
ftello - returns the offset of the current byte
ftello64 - returns the offset of the current byte (supports large files)
ftrylockfile - grant thread ownership of a file
funflush - discard buffered data
funlockfile - relinquish thread ownership of a file
fwprintf - place wide/multibyte character output on strm
fwprintf, swprintf, wprintf, vfwprintf, vswprintf, vwprintf - print wide/multibyte character formatted output
fwrite - binary output to a named stream
fwscanf - read multibyte characters from strm
fwscanf, swscanf, wscanf, vfwscanf, vswcanf, vwscanf - convert formatted wide/multibyte character input
getc - get next character (byte) from a stream
getc, getc_unlocked, getchar, getchar_unlocked, fgetc, getw - get character or word from a stream
getc_unlocked - get next character (byte) from a stream
getchar - get next character (byte) from standard input
getchar_unlocked - get next character (byte) from standard input
gets - get a line from a stream
gets, fgets - get a string from a stream
getw - get next word (integer) from a stream
getwc - get next wide character from a named stream
getwc, getwchar, fgetwc - get next wide character from a stream
getwchar - get next wide character from standard input
Intro - standard buffered input/output package
pclose - initiate pipe from a process
popen, pclose - initiate pipe to/from a process
printf - place print output on standard output
putc - put a character on a stream
putc, putc_unlocked, putchar, putchar_unlocked, fputc, putw - put character or word on a stream
putc_unlocked - put a character on a stream
putchar - put a character on a stream
putchar_unlocked - put a character on a stream
puts - put a string on the standard ouput stream
puts, fputs - put a string on a stream
putw - put a word on a stream
putwc - put wide character on a named stream
putwc, putwchar, fputwc - put wide character on a stream
putwchar - put wide character on standard output
rewind - reposition a file pointer in a stream and clear error indicator
scanf - convert formatted input read from the standard input stream
setbuf, setvbuf - assign buffering to a stream
setvbuf - assign buffering to a stream
snprintf - place print output up to n chars in character array
sprintf - place print output in character array
sscanf - convert formatted input read from a character string
stderr - standard error file
stdin - standard input file
stdio - standard I/0
stdout - standard output file
swprintf - place wide/multibyte character output in character array
swscanf - read from a wide character string
system - issue a shell command
tempnam - create a name for a temporary file
tmpfile - create a temporary file
tmpfile, tmpfile64 - create a temporary file
tmpfile64 - create a temporary file (supports large files)
tmpnam, tempnam - create a name for a temporary file
ungetc - push character back onto input stream
ungetwc - push wchar_t character back into input stream
vfprintf - place print output on strm
vfscanf - convert formatted input read from a named stream
vfsprintf - place print output up to n chars in character array, reusing buffer
vfwprintf - place wide/multibyte character output on strm
vfwscanf - read multibyte characters from strm
vprintf - place print output on standard output
vscanf - convert formatted input read from the standard input stream
vsnprintf - place print output up to n chars in character array
vsprintf - place print output in character array
vsscanf - convert formatted input read from a character string
vswprintf - place wide/multibyte character output in character array
vswscanf - read from a wide character string
vwprintf - place wide/multibyte character output on standard output
vwscanf - read multibyte characters from standard input
widec - multibyte character I/O routines
wprintf - place wide/multibyte character output on standard output
wscanf - read multibyte characters from standard input