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#include <u.h>
#include <libc.h>
/*
* Search $PATH for an executable with the given name.
* Like in rc, mid-name slashes do not disable search.
* Should probably handle escaped colons,
* but I don't know what the syntax is.
*/
char*
searchpath(char *name)
{
char *path, *p, *next;
char *s, *ss;
int ns, l;
s = nil;
ns = 0;
if((name[0] == '.' && name[1] == '/')
|| (name[0] == '.' && name[1] == '.' && name[2] == '/')
|| (name[0] == '/')){
if(access(name, AEXEC) >= 0)
return strdup(name);
return nil;
}
path = getenv("PATH");
for(p=path; p && *p; p=next){
if((next = strchr(p, ':')) != nil)
*next++ = 0;
if(*p == 0){
if(access(name, AEXEC) >= 0){
free(s);
free(path);
return strdup(name);
}
}else{
l = strlen(p)+1+strlen(name)+1;
if(l > ns){
ss = realloc(s, l);
if(ss == nil){
free(s);
free(path);
return nil;
}
s = ss;
ns = l;
}
strcpy(s, p);
strcat(s, "/");
strcat(s, name);
if(access(s, AEXEC) >= 0){
free(path);
return s;
}
}
}
free(s);
free(path);
return nil;
}
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