Ah! I finally have a progress bar that doesn't stall the build!
- pipe size in Linux is only 8*512=4096 bytes
- pipe size is not setable
- when the feeding process spits out data faster than the eating
process can read it, then the feeding process stalls after 4KiB
of data sent to the pipe
- for us, the progress bar would spawn a sub-shell every line,
and the sub-shell would in turn spawn a 'date' command.
Which was sloooww as hell, and would cause some kind of a
starvation: the pipe was full most of the time, and the
feeding process was stalled all this time.

Now, we use internal variables and a little hack based onan offset
to determine the elapsed time. Much faster this way, but still
CPU-intensive.

 diff -urN uClibc-dist/libc/sysdeps/linux/common/bits/uClibc_touplow.h uClibc/libc/sysdeps/linux/common/bits/uClibc_touplow.h

 --- uClibc-dist/libc/sysdeps/linux/common/bits/uClibc_touplow.h   Fri Jun  3 13:30:25 2005

 +++ uClibc/libc/sysdeps/linux/common/bits/uClibc_touplow.h   Fri Jun  3 13:30:39 2005

 @@ -34,11 +34,11 @@

  /* glibc uses the equivalent of - typedef __int32_t __ctype_touplow_t; */

 -typedef __uint16_t __ctype_mask_t;

 +typedef __uint32_t __ctype_mask_t;

  #ifdef __UCLIBC_HAS_CTYPE_SIGNED__

 -typedef __int16_t __ctype_touplow_t;

 +typedef __int32_t __ctype_touplow_t;

  #define __UCLIBC_CTYPE_B_TBL_OFFSET       128

  #define __UCLIBC_CTYPE_TO_TBL_OFFSET      128