Return to scanf.tbl CVS log

Up to [Research Unix] / researchv10no / cmd / lcc / ph

researchv10 Norman

                scanf format string decision tree
                ----- ------ ------ -------- ----

misc:
    extra arguments are ignored


d
    size indicator:
        h   pointer to short int
        l   pointer to long int
        L   UNDEFINED
    conversion:
        signed integer (same as strtol base 10)
        argument is pointer to int

i
    size indicator:
        h   pointer to short int
        l   pointer to long int
        L   UNDEFINED
    conversion:
        signed integer (same as strtol base 0)
        argument is pointer to int

o
    size indicator:
        h   pointer to unsigned short
        l   pointer to unsigned long
        L   UNDEFINED
    conversion:
        unsigned integer (same as strtoul base 8)
        argument is pointer to unsigned int

u
    size indicator:
        h   pointer to unsigned short
        l   pointer to unsigned long
        L   UNDEFINED
    conversion:
        unsigned integer (same as strtoul base 10)
        argument is pointer to unsigned int

x,X
    size indicator:
        h   pointer to unsigned short
        l   pointer to unsigned long
        L   UNDEFINED
    conversion:
    argument is pointer to float

s
    size indicator:
        h   UNDEFINED
        l   UNDEFINED
        L   UNDEFINED
    conversion:
        sequence of non-whitespace characters

[
    size indicator:
        h   UNDEFINED
        l   UNDEFINED
        L   UNDEFINED
    conversion:
        matches non-empty set of characters fromthe "scanset"
        argument is pointer to array large enough to recieve input string
        scanset:
            all characters between [ and  ]
            all characters not between [^ and ]
            the beginning sequences [] and [^] mean that ] is in the list
            '-' is implementation defined unless as [-   [^-   []-   or [^]-
            chargument is char *

c
    size indicator:
        h   UNDEFINED
        l   UNDEFINED
        L   UNDEFINED
    conversion:
        match characters up to field width
        default if no width is 1
        no null character is added
        argument is char *
    
p
    size indicator:
        h   UNDEFINED
        l   UNDEFINED
        L   UNDEFINED
    conversion:
        matches text produced by printf %p
        printf -> scanf with %p must produce the same pointer back
        argument is pointer to void *

n
    size indicator:
        h   pointer to short int
        l   pointer to long int
        L   UNDEFINED
    conversion:
        no input consumed and argument count not incremented
        argument is pointer to int
        write number of characters consumed

misc:
    %% is escape to match % in input
    width specifies max characters matched
    whitespace means to skip leading white space up to end of input
    multibyte characters means to read as long as match occurs (no assignment)
    input conversion is processed as:
        skip whitespace unless there is a c, [, or n specifier
        read an item fromthe input unless processing an 'n' specifier
        read longest possible match up to width specifier
        if no characters read, it is a matching failure
        * suppresses assignment 
    success leaves trailing whitespace unless there is whiatespace
            at the end of the directive
    input failure or matching failure leave next character on the input
    EOF returned if end of input before any conversions
    return number of conversions performed, may be less than
        requeted if matchin or input failure occurs

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.