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Created June 1, 2012 19:23
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diff --git a/doc/api/child_process.markdown b/doc/api/child_process.markdown
index 18be2f6..fa3a52c 100644
--- a/doc/api/child_process.markdown
+++ b/doc/api/child_process.markdown
@@ -245,6 +245,7 @@ there is no IPC channel keeping it alive. When calling this method the
* `args` {Array} List of string arguments
* `options` {Object}
* `cwd` {String} Current working directory of the child process
+ * `stdio` {Array|String} Child's stdio configuration. (See below)
* `customFds` {Array} **Deprecated** File descriptors for the child to use
for stdio. (See below)
* `env` {Object} Environment key-value pairs
@@ -336,6 +337,45 @@ spawning the process with an empty environment rather than using
`process.env`. This due to backwards compatibility issues with a deprecated
API.
+The 'stdio' option to `child_process.spawn()` is an array where each
+index corresponds to a fd in the child. The value is one of the following:
+
+1. `null`, `undefined` - Use default value. For 0,1,2 stdios this is the same
+ as `'pipe'`. For any higher value, `'ignore'`
+2. `'ignore'` - Open the fd in the child, but do not expose it to the parent
+3. `'pipe'` - Open the fd and expose as a `Stream` object to parent.
+4. `'ipc'` - Create IPC channel for passing messages/file descriptors between
+ parent and child.
+ Note: A ChildProcess may have at most *one* IPC stdio file descriptor.
+ Setting this option enables the ChildProcess.send() method. If the
+ child writes JSON messages to this file descriptor, then this will trigger
+ ChildProcess.on('message'). If the child is a Node.js program, then
+ the presence of an IPC channel will enable process.send() and
+ process.on('message')
+5. positive integer - Share corresponding fd with child
+6. Any TTY, TCP, File stream - Share corresponding stream with child
+
+As a shorthand, the `stdio` argument may also be one of the following
+strings, rather than an array:
+
+* `ignore` - `['ignore', 'ignore', 'ignore']`
+* `pipe` - `['pipe', 'pipe', 'pipe']`
+* `inherit` - `[process.stdin, process.stdout, process.stderr]` or `[0,1,2]`
+
+Example:
+
+ var spawn = require('child_process').spawn;
+
+ // Child will use parent's stdios
+ spawn('prg', [], { stdio: 'inherit' });
+
+ // Spawn child sharing only stderr
+ spawn('prg', [], { stdio: ['pipe', 'pipe', process.stderr] });
+
+ // Open an extra fd=4, to interact with programs present a
+ // startd-style interface.
+ spawn('prg', [], { stdio: ['pipe', null, null, null, 'pipe'] });
+
There is a deprecated option called `customFds` which allows one to specify
specific file descriptors for the stdio of the child process. This API was
not portable to all platforms and therefore removed.
@@ -354,8 +394,9 @@ See also: `child_process.exec()` and `child_process.fork()`
* `command` {String} The command to run, with space-separated arguments
* `options` {Object}
* `cwd` {String} Current working directory of the child process
+ * `stdio` {Array|String} Child's stdio configuration. (See above)
* `customFds` {Array} **Deprecated** File descriptors for the child to use
- for stdio. (See below)
+ for stdio. (See above)
* `env` {Object} Environment key-value pairs
* `setsid` {Boolean}
* `encoding` {String} (Default: 'utf8')
@@ -411,8 +452,9 @@ the child process is killed.
* `args` {Array} List of string arguments
* `options` {Object}
* `cwd` {String} Current working directory of the child process
+ * `stdio` {Array|String} Child's stdio configuration. (See above)
* `customFds` {Array} **Deprecated** File descriptors for the child to use
- for stdio. (See below)
+ for stdio. (See above)
* `env` {Object} Environment key-value pairs
* `setsid` {Boolean}
* `encoding` {String} (Default: 'utf8')
@@ -436,8 +478,6 @@ leaner than `child_process.exec`. It has the same options.
* `args` {Array} List of string arguments
* `options` {Object}
* `cwd` {String} Current working directory of the child process
- * `customFds` {Array} **Deprecated** File descriptors for the child to use
- for stdio. (See below)
* `env` {Object} Environment key-value pairs
* `setsid` {Boolean}
* `encoding` {String} (Default: 'utf8')
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