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See link 2 for a similar problem. Any other hard links to the file as created using link 2 are unaffected. Open 13 file descriptors for oldpath are also unaffected. In this case , newpath must either not exist, or it must specify an empty directory. This happens automatically when output is redirected to a file and the command is run directly instead of attaching. This records the time difference between the beginning of successive system calls. This records the time difference between the beginning and the end of each system call.

These structures are very common in calls and so the default behavior displays a reasonable subset of structure members. Use this option to get all of the gory details. The default qualifier is trace.

Using an exclamation mark negates the set of values. In addition, the special values all and none have the obvious meanings. Note that some shells use the exclamation point for history expansion even inside quoted arguments.

If so, you must escape the exclamation point with a backslash. The -c option is useful for determining which system calls might be useful to trace. Betchya woulda forgot that one. This is useful for watching the fork, wait, and exec steps of a process. This option has the effect of causing all arguments to be printed in hexadecimal.

Use filename. This is convenient for piping the debugging output to a program without affecting the redirections of executed programs. This is useful for overriding the default heuristic for guessing how much time is spent in mere measuring when timing system calls using the -c option. The accuracy of the heuristic can be gauged by timing a given program run without trac- ing using time 1 and comparing the accumulated system call time to the total produced using -c.

Multiple -p options can be used to attach to up to 32 processes in addition to command which is optional if at least one -p option is given. Note that filenames are not considered strings and are always printed in full. Search this site. Coder's Career. My Favorite Blog. Ideas to catch a mood. Medical angle. Space War. Word Entry. Linux 2. Understand Load Average. Mysql gone away. Mysqldump and Cron for mysql backup. The C10K problems. When you are using Linux command line frequently, using the history effectively can be a major productivity boost.

Repeat previous command quickly using 4 different methods Sometime you may end up repeating the previous commands for various reasons.