strace — Trace System Calls and Signals.Summary: In the simplest case strace runs the specified command until it exits. It intercepts and records the system calls which are called by a process and the signals which are received by a process. The name of each system call, its arguments and its return value are printed. strace is a useful diagnostic, instructional, and debugging tool. Examples:
$ strace sleep 1 -- Trace all Sys call of 'sleep' command. $ strace ls -- Trace all Sys call of 'ls' command. $ strace -i sleep 1 -- Print the value of the Instruction Pointer at every sys call. $ strace -r sleep 1 -- Print a relative time-stamp with each line of the trace. $ strace -t sleep 1 -- Prefix each line of the trace with the time of day. $ strace -T sleep 1 -- Show time spent on each call. $ strace -o file sleep 1 -- Redirect the output to a file. $ strace -c ls -- Count time, calls, and errors for each system call and report a summary on program exit. $ strace -xx myprg -- Print all strings in HEX format. $ strace -e trace=file ls -- Trace all system calls which take a filename as an argument. $ strace -e trace=process ls -- Trace all system calls which involve process management. $ sleep 60 & -- Dummy background Job. $ strace -p 1234 -- Attach to the process with the PID 1234 (use dummy job's Pid) and trace.
Read: man strace