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#include <stdio.h>
#include "popen.h"
#include <io.h>
#include <string.h>
#include <process.h>
static char template[] = "piXXXXXX";
typedef enum { unopened = 0, reading, writing } pipemode;
static
struct {
char *command;
char *name;
pipemode pmode;
} pipes[_NFILE];
FILE *
popen( char *command, char *mode ) {
FILE *current;
char *name;
int cur;
pipemode curmode;
/*
** decide on mode.
*/
if(strcmp(mode,"r") == 0)
curmode = reading;
else if(strcmp(mode,"w") == 0)
curmode = writing;
else
return NULL;
/*
** get a name to use.
*/
if((name = tempnam(".","pip"))==NULL)
return NULL;
/*
** If we're reading, just call system to get a file filled with
** output.
*/
if(curmode == reading) {
char cmd[256];
sprintf(cmd,"%s > %s",command,name);
system(cmd);
if((current = fopen(name,"r")) == NULL)
return NULL;
} else {
if((current = fopen(name,"w")) == NULL)
return NULL;
}
cur = fileno(current);
pipes[cur].name = name;
pipes[cur].pmode = curmode;
pipes[cur].command = strdup(command);
return current;
}
int
pclose( FILE * current) {
int cur = fileno(current),rval;
/*
** check for an open file.
*/
if(pipes[cur].pmode == unopened)
return -1;
if(pipes[cur].pmode == reading) {
/*
** input pipes are just files we're done with.
*/
rval = fclose(current);
unlink(pipes[cur].name);
} else {
/*
** output pipes are temporary files we have
** to cram down the throats of programs.
*/
char command[256];
fclose(current);
sprintf(command,"%s < %s",pipes[cur].command,pipes[cur].name);
rval = system(command);
unlink(pipes[cur].name);
}
/*
** clean up current pipe.
*/
pipes[cur].pmode = unopened;
free(pipes[cur].name);
free(pipes[cur].command);
return rval;
}
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