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ffs()

Find the first bit set in a bit string

Synopsis:

#include <strings.h>

int ffs( int value );

Arguments:

value
The bit string.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The ffs() function finds the first bit set in value and returns the index of that bit. Bits are numbered starting from 1, starting at the rightmost bit.

Returns:

The index of the first bit set, or 0 if value is zero.

Classification:

POSIX 1003.1 XSI

Safety:
Cancellation point No
Interrupt handler No
Signal handler Yes
Thread Yes