Conversion Specifiers
In the descriptions that follow, I summarize the match pattern and conversion rules for each valid conversion specifier. w stands for the field width you specify, or the indicated default value if you specify no field width. ptr stands for the next argument to consume in the varying length argument list: c — stores w characters (default is 1) in the array of char whose first element is pointed at by ptr. It does not skip leading whitespace. d — converts the integer input field by calling strtol with a base of 10, then stores the result in the int pointed at by ptr. hd — converts the integer input field by calling strtol with a base of 10, then stores the result in the short pointed at by ptr. ld — converts the integer input field by calling strtol with a base of 10, then stores the result in the long pointed at by ptr. e — converts the floating point input field by calling strtod, then stores the result in the float pointed at by ptr. le — converts the floating point input field by calling strtod, then stores the result in the double pointed at by ptr. Le — converts the floating point input field by calling strtod, then stores the result in the long double pointed at by ptr. E — is the same as e. lE — is the same as le. LE — is the same as Le. f — is the same as e. lf — is the same as le. Lf — is the same as Le. g — is the same as e. lg — is the same as le. Lg — is the same as Le. G — is the same as e. lG — is the same as le. LG — is the same as Le i — converts the integer input field by calling strtol with a base of zero, then stores the result in the int pointed at by ptr. (A base of zero lets you write input that begins with 0, 0x, or 0X to specify an actual numeric base other than 10.) hi — converts the integer input field by calling strtol with a base of zero, then stores the result in the short pointed at by ptr. i — converts the integer input field by calling strtol with a base of zero, then stores the result in the long pointed at by ptr. n — converts no input, but stores the cumulative number of matched input characters in the int pointed at by ptr. It does not skip leading whitespace. hn — converts no input, but stores the cumulative number of matched input characters in the short pointed at by ptr. It does not skip leading whitespace. ln — converts no input, but stores the cumulative number of matched input characters in the long pointed at by ptr. It does not skip leading whitespace. o — converts the integer input field by calling strtoul with a base of eight, then stores the result in the unsigned int pointed at by ptr. ho — converts the integer input field by calling strtoul with a base of eight, then stores the result in the unsigned short pointed at by ptr. lo — converts the integer input field by calling strtoul with a base of eight, then stores the result in the unsigned long pointed at by ptr. p — converts the pointer input field, then stores the result in the void * pointed at by ptr. Each implementation defines its pointer input field to be consistent with pointers written by the print function. s — stores up to w non-whitespace characters (default is the rest of the input) in the array of char pointed at by ptr. It first skips leading whitespace, and it always stores a null character after any input. u — converts the integer input field by calling strtoul with a base of 10, then stores the result in the unsigned int pointed at by ptr. hu — converts the integer input field by calling strtoul with a base of 10, then stores the result in the unsigned short pointed at by ptr. lu — converts the integer input field by calling strtoul with a base of 10, then stores the result in the unsigned long pointed at by ptr. x — converts the integer input field by calling strtoul with a base of 16, then stores the result in the unsigned int pointed at by ptr. hx — converts the integer input field by calling strtoul with a base of 16, then stores the result in the unsigned short pointed at by ptr. lx — converts the integer input field by calling strtoul with a base of 16, then stores the result in the unsigned long pointed at by ptr. X — is the same as x. hX — is the same as hx. lX — is the same as lx. % — converts no input, but matches a percent character. (%)