Rebecca Turner
507fc53e37
PR-URL: https://github.com/nodejs/node/pull/3599 Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com> |
9 years ago | |
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.. | ||
LICENSE | deps: upgrade npm to 3.3.6 | 9 years ago |
README.md | deps: upgrade npm to 3.3.6 | 9 years ago |
debuglog.js | deps: upgrade npm to 3.3.6 | 9 years ago |
package.json | deps: upgrade npm to 3.3.10 | 9 years ago |
README.md
debuglog - backport of util.debuglog() from node v0.11
To facilitate using the util.debuglog()
function that will be available when
node v0.12 is released now, this is a copy extracted from the source.
require('debuglog')
Return util.debuglog
, if it exists, otherwise it will return an internal copy
of the implementation from node v0.11.
debuglog(section)
section
{String} The section of the program to be debugged- Returns: {Function} The logging function
This is used to create a function which conditionally writes to stderr
based on the existence of a NODE_DEBUG
environment variable. If the
section
name appears in that environment variable, then the returned
function will be similar to console.error()
. If not, then the
returned function is a no-op.
For example:
var debuglog = util.debuglog('foo');
var bar = 123;
debuglog('hello from foo [%d]', bar);
If this program is run with NODE_DEBUG=foo
in the environment, then
it will output something like:
FOO 3245: hello from foo [123]
where 3245
is the process id. If it is not run with that
environment variable set, then it will not print anything.
You may separate multiple NODE_DEBUG
environment variables with a
comma. For example, NODE_DEBUG=fs,net,tls
.