These functions provide an alternative to the C++ stream-based IO classes.
| clearerr | clears errors |
| fclose | close a file |
| feof | true if at the end-of-file |
| ferror | checks for a file error |
| fflush | writes the contents of the output buffer |
| fgetc | get a character from a stream |
| fgetpos | get the file position indicator |
| fgets | get a string of characters from a stream |
| fopen | open a file |
| fprintf | print formatted output to a file |
| fputc | write a character to a file |
| fputs | write a string to a file |
| fread | read from a file |
| freopen | open an existing stream with a different name |
| fscanf | read formatted input from a file |
| fseek | move to a specific location in a file |
| fsetpos | move to a specific location in a file |
| ftell | returns the current file position indicator |
| fwrite | write to a file |
| getc | read a character from a file |
| getchar | read a character from stdin |
| gets | read a string from stdin |
| perror | displays a string version of the current error to stderr |
| printf | write formatted output to stdout |
| putc | write a character to a stream |
| putchar | write a character to stdout |
| puts | write a string to stdout |
| remove | erase a file |
| rename | rename a file |
| rewind | move the file position indicator to the beginning of a file |
| scanf | read formatted input from stdin |
| setbuf | set the buffer for a specific stream |
| setvbuf | set the buffer and size for a specific stream |
| snprintf | write formated output to a buffer (with bound checking) |
| sprintf | write formatted output to a buffer |
| sscanf | read formatted input from a buffer |
| tmpfile | return a pointer to a temporary file |
| tmpnam | return a unique filename |
| ungetc | puts a character back into a stream |
| vprintf, vfprintf, and vsprintf | write formatted output with variable argument lists |
| vscanf, vfscanf, and vsscanf | gets formatted input from stdin with variable argument lists |