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macosbashscriptinglaunchd

How can I add arguments to OSX launchd plist to pipe output to a log file?


I have tried many different variation on this but just can't get it to work.

I have a plist file:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
        <key>Label</key>
        <string>com.ilium007.handbrake</string>
        <key>ProgramArguments</key>
        <array>
                <string>/bin/bash</string>
                <string>/Users/ilium007/support/scripts/handbrake/handbrake.sh &gt;&gt; /Users/ilium007/support/scripts/handbrake/logs/handbrake_encode.log</string>
                <!--<string>&gt;&gt;</string>-->
                <!--<string>/Users/ilium007/support/scripts/handbrake/logs/handbrake_encode.log</string>-->
        </array>
        <key>RunAtLoad</key>
        <true/>
        <key>StartInterval</key>
        <integer>60</integer>
</dict>
</plist>

Note the comments in there.

I want to pipe output from the handbrake.sh script to a log file and have tried to do so but keep getting A "no such file" error in system.log on OSX.

Nov  3 18:03:54 macmini com.ilium007.handbrake[15348]: /bin/bash: /Users/ilium007/support/scripts/handbrake/handbrake.sh >> /Users/ilium007/support/scripts/handbrake/logs/handbrake_encode.log: No such file or directory Nov  3 18:03:54 macmini com.apple.launchd.peruser.501[162] (com.ilium007.handbrake[15348]): Exited with code: 127

If I change the plist to the following, it runs but I get no log so I assume it is only running the first argument:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
        <key>Label</key>
        <string>com.ilium007.handbrake</string>
        <key>ProgramArguments</key>
        <array>
                <string>/bin/bash</string>
                <string>/Users/ilium007/support/scripts/handbrake/handbrake.sh</string>
                <string>&gt;&gt;</string>
                <string>/Users/ilium007/support/scripts/handbrake/logs/handbrake_encode.log</string>
        </array>
        <key>RunAtLoad</key>
        <true/>
        <key>StartInterval</key>
        <integer>60</integer>
</dict>
</plist>

The command that I would like to run via launchd is:

/Users/ilium007/support/scripts/handbrake/handbrake.sh >> /Users/ilium007/support/scripts/handbrake/logs/handbrake_encode.log

Nothing ever appears in the log file. But if I run that command from the terminal I get content in the log. Any help would be appreciated.


Solution

  • >> is a shell operator, not a program argument, and launchd doesn't pass its commands through a shell (unless you force it, as in @Lauri's answer). But launchd does have its own option for redirecting stdout:

    <key>StandardOutPath</key>
    <string>/Users/ilium007/support/scripts/handbrake/logs/handbrake_encode.log</string>
    

    Note that it automatically appends (equivalent to >>, not >). You can also redirect stderr with the StandardErrorPath key. One thing you cannot do is use ~ (as in ~/support/scripts/handbrake/logs/handbrake_encode.log) -- that, again, is a shell feature that launchd doesn't emulate.