You have a number of tools at your disposal.
To match an entire string, you use strcmp():
match = strcmp(str1,str2)
match is <0 or >0 for a mismatch (str1 < str2, or str1 > str2), or 0 for a match, so you can use
if(!strcmp(command,"run"))
{
...
}
If you know the length of the substring, then you have the strncmp() function.
match = strncmp(str1, str2, size);
match is <0 or >0 for a mismatch (str1 < str2, or str1 > str2), or 0 for a match.
If you don't know where the substring is, then there is the strstr() function.
pos = strstr(str1,str2);
which returns the position of str2 within str1.
Then there is sscanf, which can be used to find parameters within a string:
int a,b,c;
if(sscanf(command,"set_coords %d %d %d",&a,&b,&c))
{
...
}
will take the string "set_coords 34 2 4983" and assign the numbers to the variables a b and c. sscanf returns the number of parameters matched.
And there are loads more.