Link Search Menu Expand Document

strace Cheat Sheet

Usage examples

strace <command>         # Trace all syscalls of a command
strace -f <command>      # Trace including all forked processes
strace -p <pid>          # Attach to a running process

# Filter/set output for specific syscall(s)
strace -e <output mode>=<syscall set>   <command>

strace -e <syscall set>   <command>
strace -e open,openat     <command>

strace -v -s1000 <command>           # Very verbose shows up to 1000 bytes of parameters
strace -x  <command>                 # Print non-ASCII parameters in hex

strace -k -e exit <command>          # Print stacktrace on each 'exit' syscall

strace -r  <command>                 # Add relative timestamp to each line (resolution: ┬Áseconds)
strace -t  <command>                 # Add timestamp to each line (resolution: seconds)
strace -tt <command>                 # Add timestamp to each line (resolution: ┬Áseconds)
strace -T  <command>                 # Print syscall duration for each syscall at the end

To get per syscall time statistics run with

strace -c <command>

Then you get a summary table like this

% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 66,75    0,003708           0      3922           read
 33,25    0,001847           0      2685           write
------ ----------- ----------- --------- --------- ----------------
100,00    0,005555           0      6607           total