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xt_ff_popen(3) Library Functions Manual xt_ff_popen(3) NAME xt_ff_popen() - Create a fast file stream connected to a process LIBRARY #include <xtend/fast-file.h> -lxtend SYNOPSIS xt_ff_t *xt_ff_popen(const char *cmd, int flags) ARGUMENTS cmd Full command to execute as the child, passed to sh(1) flags Open mode flags passed to open(3) DESCRIPTION xt_ff_popen(3) creates a pipe for interprocess communication, runs the specified command, connecting the command's standard input or standard output to the pipe, and returning a pointer to a xt_ff_t object con- nected to the other end. It behaves much like popen(3), except that it returns a fast-file xt_ff_t pointer rather than a standard I/O FILE pointer, and accepts a full set of open(3) flags rather than the fopen(3) type strings "r", "w", etc. This allows the calling program to spawn a child process and read its standard output or write to its standard input as easily as reading or writing a file. Note that the stream may be closed with xt_ff_close(3). Unlike popen(3), which must be used with pclose(3), it is not necessary to call _xt_ff_pclose(3) directly. The xt_ff_close(3) function automati- cally determines whether the stream is attached to a pipe. The xt_ff_t system is simpler than and much faster than traditional FILE on typical systems. It is intended for processing large files character-by-character, where low-level block I/O is not convenient, but FILE I/O causes a bottleneck. RETURN VALUES Pointer to a xt_ff_ile_t object on success, NULL otherwise EXAMPLES xt_ff_t *instream; if ( (instream = xt_ff_popen("xzcat file.xz", O_RDONLY)) == NULL ) { fprintf(stderr, "Failed to read xzcat file.xz.n"); exit(EX_NOINPUT); } xt_ff_close(instream); SEE ALSO xt_ff_open(3), xt_ff_close(3), popen(3), open(3) xt_ff_popen(3)
NAME | LIBRARY | SYNOPSIS | ARGUMENTS | DESCRIPTION | RETURN VALUES | EXAMPLES | SEE ALSO
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