Added wrappers err_fputc and err_fputs to catch failures in fput and fputs.
Macros err_putchar and err_puts call the new wrappers and can be used in
place of putchar and puts.
To avoid having to make millions of function calls when printing out
sequences, the code to print them in bwa_print_sam1 using putchar has
been replaced by a new version in bwa_print_seq that puts the sequence
into a buffer and then outputs the lot with err_fwrite. In testing, the
new code was slightly faster than the old version, with the added benefit
that it will stop promptly if IO problems are detected.
Rob Davies
Heng Li
Heng Li