Avoid linebreaks in LaTeX console / log output (or increase columns in terminal)

You can modify the texmf.cnf variables error_line and max_print_line, adding to the "local" texmf.cnf file, whose location depends on the distribution you're using; for TeX Live it is

/usr/local/texlive/2011/texmf.cnf

and the lines to be added are

max_print_line=1000
error_line=254
half_error_line=238

The first number is actually arbitrary, but 1000 seems to be sufficient. The error_line variable must be less than 255 and the maximum value of half_error_line is less than error_line-15

For experimenting you can also set the variables in the environment; assuming a Bash shell,

export max_print_line=1000
export error_line=254
export half_error_line=238

In MiKTeX you can use the option --max-print-line=140 to get longer log lines. This will also affect the output in the command line window but only if have enlarged it before.