difference between "sh -c" & "/usr/bin/sh"

[j773303]

does anyone know the difference between "sh -c" & "/usr/bin/sh"

I've a process shows as below: ps -ef

sh -c exec /etc/cmcluster/mqm/mq.cntl

[Peter Godron · Accepted solution]

Hi,
I believe sh -c will run the /usr/bin/sh.
Test:
$ cat a.sh
echo $PPID
sleep 10
echo $PPID

$ sh -c a.sh &
[1] 4142
$ 4142
ps -ef | grep 4142
godronpw 4143 4142 0 08:46:47 pts/ta 0:00 /usr/bin/sh a.sh
godronpw 4142 4045 0 08:46:47 pts/ta 0:00 sh -c a.sh
godronpw 4150 4045 0 08:46:53 pts/ta 0:00 grep 4142
$ 4142

[rariasn]

Hi j773303,

http://www.research.att.com/~gsf/man/man1/sh.html

rgs,

[Coolmar]

Hi, I found the following:

-c
Read commands from the command_string operand. Set the value of special parameter 0 (see Special Parameters) from the value of the command_name operand and the positional
parameters ($1, $2, and so on) in sequence from the remaining argument operands. No commands shall be read from the standard input.

I interpret that to say that "sh -c string" is the same as putting that string in a file and running it as a script:

# echo 'echo hello there' > test.script
# sh test.script
hello there

[Bill Hassell]

sh -c is almost always initiated from a script. Look at the parent process (PPID) and you'll likely see it will be an application or cron or batch script.