43.5. Redirection in C Shell: Capture Errors, Too?
The > (right angle bracket) operator redirects the standard output of a process to a file. It doesn't affect the standard error. If you're logged in and can see any messages written to standard error, that's okay:
% nroff -ms report.ms > report.out &  10316 ...Later... nroff: can't open file /hoem/jpeek/report.data
make Section 11.10
% make >& make.output &  10329 % logout ...Later... % cat make.output cc -O -c random.c cc -O -c output.c "output.c", line 46: syntax error "output.c", line 50: time_e undefined "output.c", line 50: syntax error ...
You might also use the >& operator while you're logged in and watch the output file with tail -f (Section 12.10). If you don't want the errors mixed with other output, you can split them to two files; see Section 43.1.
The C shell also has a pipe operator, |&, that redirects both standard output and standard error. It's great for running a job in the background or on another computer and mailing (Section 1.21) any output to me:
% make |& mailx -s "'make bigprog' output" firstname.lastname@example.org &  29182 29183
If I'd used plain | instead of |&, any text on the standard error wouldn't go into the mail message.
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