stdio.h

clearerr : Reset error indicators.
fclose : Close a stream.
feof : Check if End Of File has been reached.
ferror : Check for errors.
fflush : Flush a stream.
fgetc : Get next character from a stream.
fgetpos : Get position in a stream.
fgets : Get string from a stream.
fopen : Open a file.
fprintf : Print formatted data to a stream.
fputc : Write character to a stream.
fputchar : Write character to stdout.
fputs : Write string to a stream.
fread : Read block of data from a stream.
freopen : Reopen a file using a different file mode.
fscanf : Read formatted data from a stream.
fseek : Reposition stream's position indicator.
fsetpos : Reposition file pointer to a saved location.
ftell : Return the current position of the file pointer.
fwrite : Write block of data to a stream.
getc : Get the next character.
getchar : Get the next character from stdin.
gets : Get a string from stdin.
getw : Get the next int value from a stream.
perror : Print error message.
printf : Print formatted data to stdout.
putc : Write character to a stream.
putchar : Write character to stdout.
puts : Write a string to stdout.
putw : Write an integer to a stream.
remove : Delete a file.
rename : Rename a file or directory.
rewind : Reposition file pointer to the beginning of a stream.
scanf : Read formatted data from stdin.
setbuf : Change stream buffering.
setvbuf : Change stream buffering.
sprintf : Format data to a string.
sscanf : Read formatted data from a string.
tmpfile : Open a temporary file.
tmpnam : Generate a unique temporary filename.
ungetc : Push a character back into stream.